Convert.ToInt16 メソッド
定義
重要
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指定した値を 16 ビット符号付き整数に変換します。
オーバーロード
| ToInt16(Single) |
指定した単精度浮動小数点数の値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(String, IFormatProvider) |
指定したカルチャに固有の書式情報を使用して、指定した数値の文字列形式を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(Object, IFormatProvider) |
指定したカルチャに固有の書式情報を使用して、指定したオブジェクトの値を 16 ビット符号付き整数に変換します。 |
| ToInt16(UInt64) |
指定した 64 ビット符号なし整数の値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(UInt32) |
指定した 32 ビット符号なし整数の値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(UInt16) |
指定した 16 ビット符号なし整数の値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(String) |
数値の指定した文字列形式を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(String, Int32) |
指定した基数での数値の文字列形式を、等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(SByte) |
指定した 8 ビット符号付き整数の値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(Int16) |
指定した 16 ビット符号付き整数が返されます。実際の変換は行われません。 |
| ToInt16(Int64) |
指定された 64 ビット符号付き整数の値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(Int32) |
指定した 32 ビット符号付き整数の値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(Double) |
指定された倍精度浮動小数点数値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(Decimal) |
指定した 10 進数値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(DateTime) |
このメソッドを呼び出すと、必ず InvalidCastException がスローされます。 |
| ToInt16(Char) |
指定した Unicode 文字の値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(Byte) |
指定した 8 ビット符号なし整数の値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(Boolean) |
指定したブール値を等価の 16 ビット符号付き整数に変換します。 |
| ToInt16(Object) |
指定したオブジェクトの値を 16 ビット符号付き整数に変換します。 |
ToInt16(Single)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定した単精度浮動小数点数の値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(float value);public static short ToInt16 (float value);static member ToInt16 : single -> int16Public Shared Function ToInt16 (value As Single) As Shortパラメーター
- value
- Single
変換する単精度浮動小数点数。
戻り値
近似値の 16 ビット符号付き整数に丸められた value。
value が 2 つの整数のちょうど中間にある場合は、偶数が返されます。つまり、4.5 は 4 に変換され、5.5 は 6 に変換されます。
例外
value が Int16.MaxValue より大きいか、 Int16.MinValue より小さい。
例
次の例では、値の配列内の Single 各要素を 16 ビット符号付き整数に変換しようとしています。
float[] values = { Single.MinValue, -1.38e10f, -1023.299f, -12.98f,
0f, 9.113e-16f, 103.919f, 17834.191f, Single.MaxValue };
short result;
foreach (float value in values)
{
try {
result = Convert.ToInt16(value);
Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
value.GetType().Name, value, result.GetType().Name, result);
}
catch (OverflowException) {
Console.WriteLine("{0} is outside the range of the Int16 type.", value);
}
}
// The example displays the following output:
// -3.4028235E+38 is outside the range of the Int16 type.
// -1.38E+10 is outside the range of the Int16 type.
// Converted the Single value -1023.299 to the Int16 value -1023.
// Converted the Single value -12.98 to the Int16 value -13.
// Converted the Single value 0 to the Int16 value 0.
// Converted the Single value 9.113E-16 to the Int16 value 0.
// Converted the Single value 103.919 to the Int16 value 104.
// Converted the Single value 17834.191 to the Int16 value 17834.
// 3.4028235E+38 is outside the range of the Int16 type.
let values =
[| Single.MinValue; -1.38e10f; -1023.299f; -12.98f
0f; 9.113e-16f; 103.919f; 17834.191f; Single.MaxValue |]
for value in values do
try
let result = Convert.ToInt16 value
printfn $"Converted the {value.GetType().Name} value {value} to the {result.GetType().Name} value {result}."
with :? OverflowException ->
printfn $"{value} is outside the range of the Int16 type."
// The example displays the following output:
// -3.4028235E+38 is outside the range of the Int16 type.
// -1.38E+10 is outside the range of the Int16 type.
// Converted the Single value -1023.299 to the Int16 value -1023.
// Converted the Single value -12.98 to the Int16 value -13.
// Converted the Single value 0 to the Int16 value 0.
// Converted the Single value 9.113E-16 to the Int16 value 0.
// Converted the Single value 103.919 to the Int16 value 104.
// Converted the Single value 17834.191 to the Int16 value 17834.
// 3.4028235E+38 is outside the range of the Int16 type.
Dim values() As Single = { Single.MinValue, -1.38e10, -1023.299, -12.98, _
0, 9.113e-16, 103.919, 17834.191, Single.MaxValue }
Dim result As Short
For Each value As Single In values
Try
result = Convert.ToInt16(value)
Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
value.GetType().Name, value, result.GetType().Name, result)
Catch e As OverflowException
Console.WriteLine("{0} is outside the range of the Int16 type.", value)
End Try
Next
' The example displays the following output:
' -3.402823E+38 is outside the range of the Int16 type.
' -1.38E+10 is outside the range of the Int16 type.
' Converted the Single value -1023.299 to the Int16 value -1023.
' Converted the Single value -12.98 to the Int16 value -13.
' Converted the Single value 0 to the Int16 value 0.
' Converted the Single value 9.113E-16 to the Int16 value 0.
' Converted the Single value 103.919 to the Int16 value 104.
' Converted the Single value 17834.19 to the Int16 value 17834.
' 3.402823E+38 is outside the range of the Int16 type.
こちらもご覧ください
適用対象
ToInt16(String, IFormatProvider)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定したカルチャに固有の書式情報を使用して、指定した数値の文字列形式を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::String ^ value, IFormatProvider ^ provider);public static short ToInt16 (string value, IFormatProvider provider);public static short ToInt16 (string? value, IFormatProvider? provider);static member ToInt16 : string * IFormatProvider -> int16Public Shared Function ToInt16 (value As String, provider As IFormatProvider) As Shortパラメーター
- value
- String
変換する数値を含んだ文字列。
- provider
- IFormatProvider
カルチャ固有の書式情報を提供するオブジェクト。
戻り値
value の数値と等価の 16 ビット符号付き整数。value が null の場合は 0 (ゼロ)。
例外
value は、オプションの符号とそれに続く数字 (0 ～ 9) のシーケンスで構成されていません。
value は、 Int16.MinValue より小さいか、Int16.MaxValue より大きい数値 を表します。
例
次の例では、 オブジェクトを使用して、 メソッドを使用して 16 ビット整数 ToInt16 の文字列表現を IFormatProvider 変換します。
// Example of the Convert::ToInt16( String* ) and
// Convert::ToInt16( String*, IFormatProvider* ) methods.
using namespace System;
using namespace System::Globalization;
const __wchar_t * protoFmt = L"{0,-20}{1,-20}{2}";
// Get the exception type name; remove the namespace prefix.
String^ GetExceptionType( Exception^ ex )
{
String^ exceptionType = ex->GetType()->ToString();
return exceptionType->Substring( exceptionType->LastIndexOf( '.' ) + 1 );
}
void ConvertToInt16( String^ numericStr, IFormatProvider^ provider )
{
Object^ defaultValue;
Object^ providerValue;
// Convert numericStr to Int16 without a format provider.
try
{
defaultValue = Convert::ToInt16( numericStr );
}
catch ( Exception^ ex )
{
defaultValue = GetExceptionType( ex );
}
// Convert numericStr to Int16 with a format provider.
try
{
providerValue = Convert::ToInt16( numericStr, provider );
}
catch ( Exception^ ex )
{
providerValue = GetExceptionType( ex );
}
Console::WriteLine( gcnew String( protoFmt ), numericStr, defaultValue, providerValue );
}
int main()
{
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
NumberFormatInfo^ provider = gcnew NumberFormatInfo;
// These properties affect the conversion.
provider->NegativeSign = "neg ";
provider->PositiveSign = "pos ";
// These properties do not affect the conversion.
// The input string cannot have decimal and group separators.
provider->NumberDecimalSeparator = ".";
provider->NumberGroupSeparator = ",";
array<Int32>^sizes = {3};
provider->NumberGroupSizes = sizes;
provider->NumberNegativePattern = 0;
Console::WriteLine( "This example of\n"
" Convert::ToInt16( String* ) and \n"
" Convert::ToInt16( String*, IFormatProvider* ) "
"\ngenerates the following output. It converts "
"several strings to \nshort values, using "
"default formatting or a NumberFormatInfo object.\n" );
Console::WriteLine( gcnew String( protoFmt ), "String to convert", "Default/exception", "Provider/exception" );
Console::WriteLine( gcnew String( protoFmt ), "-----------------", "-----------------", "------------------" );
// Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider );
ConvertToInt16( "+12345", provider );
ConvertToInt16( "pos 12345", provider );
ConvertToInt16( "-12345", provider );
ConvertToInt16( "neg 12345", provider );
ConvertToInt16( "12345.", provider );
ConvertToInt16( "12,345", provider );
ConvertToInt16( "(12345)", provider );
ConvertToInt16( "32768", provider );
ConvertToInt16( "-32769", provider );
}
/*
This example of
Convert::ToInt16( String* ) and
Convert::ToInt16( String*, IFormatProvider* )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.
String to convert Default/exception Provider/exception
----------------- ----------------- ------------------
12345 12345 12345
+12345 12345 FormatException
pos 12345 FormatException 12345
-12345 -12345 FormatException
neg 12345 FormatException -12345
12345. FormatException FormatException
12,345 FormatException FormatException
(12345) FormatException FormatException
32768 OverflowException OverflowException
-32769 OverflowException FormatException
*/
// Example of the Convert.ToInt16( string ) and
// Convert.ToInt16( string, IFormatProvider ) methods.
using System;
using System.Globalization;
class ToInt16ProviderDemo
{
static string format = "{0,-20}{1,-20}{2}";
// Get the exception type name; remove the namespace prefix.
static string GetExceptionType( Exception ex )
{
string exceptionType = ex.GetType( ).ToString( );
return exceptionType.Substring(
exceptionType.LastIndexOf( '.' ) + 1 );
}
static void ConvertToInt16( string numericStr,
IFormatProvider provider )
{
object defaultValue;
object providerValue;
// Convert numericStr to Int16 without a format provider.
try
{
defaultValue = Convert.ToInt16( numericStr );
}
catch( Exception ex )
{
defaultValue = GetExceptionType( ex );
}
// Convert numericStr to Int16 with a format provider.
try
{
providerValue = Convert.ToInt16( numericStr, provider );
}
catch( Exception ex )
{
providerValue = GetExceptionType( ex );
}
Console.WriteLine( format, numericStr,
defaultValue, providerValue );
}
public static void Main( )
{
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
NumberFormatInfo provider = new NumberFormatInfo();
// These properties affect the conversion.
provider.NegativeSign = "neg ";
provider.PositiveSign = "pos ";
// These properties do not affect the conversion.
// The input string cannot have decimal and group separators.
provider.NumberDecimalSeparator = ".";
provider.NumberGroupSeparator = ",";
provider.NumberGroupSizes = new int[ ] { 3 };
provider.NumberNegativePattern = 0;
Console.WriteLine("This example of\n" +
" Convert.ToInt16( string ) and \n" +
" Convert.ToInt16( string, IFormatProvider ) " +
"\ngenerates the following output. It converts " +
"several strings to \nshort values, using " +
"default formatting or a NumberFormatInfo object.\n" );
Console.WriteLine( format, "String to convert",
"Default/exception", "Provider/exception" );
Console.WriteLine( format, "-----------------",
"-----------------", "------------------" );
// Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider );
ConvertToInt16( "+12345", provider );
ConvertToInt16( "pos 12345", provider );
ConvertToInt16( "-12345", provider );
ConvertToInt16( "neg 12345", provider );
ConvertToInt16( "12345.", provider );
ConvertToInt16( "12,345", provider );
ConvertToInt16( "(12345)", provider );
ConvertToInt16( "32768", provider );
ConvertToInt16( "-32769", provider );
}
}
/*
This example of
Convert.ToInt16( string ) and
Convert.ToInt16( string, IFormatProvider )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.
String to convert Default/exception Provider/exception
----------------- ----------------- ------------------
12345 12345 12345
+12345 12345 FormatException
pos 12345 FormatException 12345
-12345 -12345 FormatException
neg 12345 FormatException -12345
12345. FormatException FormatException
12,345 FormatException FormatException
(12345) FormatException FormatException
32768 OverflowException OverflowException
-32769 OverflowException FormatException
*/
// Example of the Convert.ToInt16( string ) and
// Convert.ToInt16( string, IFormatProvider ) methods.
open System
open System.Globalization
let format obj1 obj2 obj3 = printfn $"{obj1,-20}{obj2,-20}{obj3}"
// Get the exception type name; remove the namespace prefix.
let getExceptionType (ex: exn) =
let exceptionType = ex.GetType() |> string
exceptionType.Substring(exceptionType.LastIndexOf '.' + 1)
let convertToInt16 (numericStr: string) (provider: IFormatProvider) =
// Convert numericStr to Int16 without a format provider.
let defaultValue =
try
Convert.ToInt16 numericStr
|> string
with ex ->
getExceptionType ex
// Convert numericStr to Int16 with a format provider.
let providerValue =
try
Convert.ToInt16(numericStr, provider)
|> string
with ex ->
getExceptionType ex
format numericStr defaultValue providerValue
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
let provider = NumberFormatInfo()
// These properties affect the conversion.
provider.NegativeSign <- "neg "
provider.PositiveSign <- "pos "
// These properties do not affect the conversion.
// The input string cannot have decimal and group separators.
provider.NumberDecimalSeparator <- "."
provider.NumberGroupSeparator <- ","
provider.NumberGroupSizes <- [| 3 |]
provider.NumberNegativePattern <- 0
printfn
"""This example of
Convert.ToInt16( string ) and
Convert.ToInt16( string, IFormatProvider )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.
"""
format "String to convert" "Default/exception" "Provider/exception"
format "-----------------" "-----------------" "------------------"
// Convert strings, with and without an IFormatProvider.
convertToInt16 "12345" provider
convertToInt16 "+12345" provider
convertToInt16 "pos 12345" provider
convertToInt16 "-12345" provider
convertToInt16 "neg 12345" provider
convertToInt16 "12345." provider
convertToInt16 "12,345" provider
convertToInt16 "(12345)" provider
convertToInt16 "32768" provider
convertToInt16 "-32769" provider
// This example of
// Convert.ToInt16( string ) and
// Convert.ToInt16( string, IFormatProvider )
// generates the following output. It converts several strings to
// short values, using default formatting or a NumberFormatInfo object.
//
// String to convert Default/exception Provider/exception
// ----------------- ----------------- ------------------
// 12345 12345 12345
// +12345 12345 FormatException
// pos 12345 FormatException 12345
// -12345 -12345 FormatException
// neg 12345 FormatException -12345
// 12345. FormatException FormatException
// 12,345 FormatException FormatException
// (12345) FormatException FormatException
// 32768 OverflowException OverflowException
// -32769 OverflowException FormatException
' Example of the Convert.ToInt16( String ) and
' Convert.ToInt16( String, IFormatProvider ) methods.
Imports System.Globalization
Module ToInt16ProviderDemo
Dim format As String = "{0,-20}{1,-20}{2}"
' Get the exception type name; remove the namespace prefix.
Function GetExceptionType( ex As Exception ) As String
Dim exceptionType As String = ex.GetType( ).ToString( )
Return exceptionType.Substring( _
exceptionType.LastIndexOf( "."c ) + 1 )
End Function
Sub ConvertToInt16( numericStr As String, _
provider As IFormatProvider )
Dim defaultValue As Object
Dim providerValue As Object
' Convert numericStr to Int16 without a format provider.
Try
defaultValue = Convert.ToInt16( numericStr )
Catch ex As Exception
defaultValue = GetExceptionType( ex )
End Try
' Convert numericStr to Int16 with a format provider.
Try
providerValue = Convert.ToInt16( numericStr, provider )
Catch ex As Exception
providerValue = GetExceptionType( ex )
End Try
Console.WriteLine( format, numericStr, _
defaultValue, providerValue )
End Sub
Sub Main( )
' Create a NumberFormatInfo object and set several of its
' properties that apply to numbers.
Dim provider As NumberFormatInfo = new NumberFormatInfo( )
' These properties affect the conversion.
provider.NegativeSign = "neg "
provider.PositiveSign = "pos "
' These properties do not affect the conversion.
' The input string cannot have decimal and group separators.
provider.NumberDecimalSeparator = "."
provider.NumberGroupSeparator = ","
provider.NumberGroupSizes = New Integer( ) { 3 }
provider.NumberNegativePattern = 0
Console.WriteLine( "This example of" & vbCrLf & _
" Convert.ToInt16( String ) and " & vbCrLf & _
" Convert.ToInt16( String, IFormatProvider ) " & _
vbCrLf & "generates the following output. It " & _
"converts several strings to " & vbCrLf & "Short " & _
"values, using default formatting " & _
"or a NumberFormatInfo object." & vbCrLf )
Console.WriteLine( format, "String to convert", _
"Default/exception", "Provider/exception" )
Console.WriteLine( format, "-----------------", _
"-----------------", "------------------" )
' Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider )
ConvertToInt16( "+12345", provider )
ConvertToInt16( "pos 12345", provider )
ConvertToInt16( "-12345", provider )
ConvertToInt16( "neg 12345", provider )
ConvertToInt16( "12345.", provider )
ConvertToInt16( "12,345", provider )
ConvertToInt16( "(12345)", provider )
ConvertToInt16( "32768", provider )
ConvertToInt16( "-32769", provider )
End Sub
End Module
' This example of
' Convert.ToInt16( String ) and
' Convert.ToInt16( String, IFormatProvider )
' generates the following output. It converts several strings to
' Short values, using default formatting or a NumberFormatInfo object.
'
' String to convert Default/exception Provider/exception
' ----------------- ----------------- ------------------
' 12345 12345 12345
' +12345 12345 FormatException
' pos 12345 FormatException 12345
' -12345 -12345 FormatException
' neg 12345 FormatException -12345
' 12345. FormatException FormatException
' 12,345 FormatException FormatException
' (12345) FormatException FormatException
' 32768 OverflowException OverflowException
' -32769 OverflowException FormatException
注釈
provider は、 IFormatProvider オブジェクトを取得するインスタンスです NumberFormatInfo 。 オブジェクトは NumberFormatInfo 、 の形式に関するカルチャ固有の value情報を提供します。 が のnull場合providerは、NumberFormatInfo現在のカルチャの が使用されます。
変換が失敗した場合に例外を処理しない場合は、代わりに メソッドを Int16.TryParse 呼び出すことができます。 変換が Boolean 成功したか失敗したかを示す値を返します。
こちらもご覧ください
適用対象
ToInt16(Object, IFormatProvider)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定したカルチャに固有の書式情報を使用して、指定したオブジェクトの値を 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::Object ^ value, IFormatProvider ^ provider);public static short ToInt16 (object value, IFormatProvider provider);public static short ToInt16 (object? value, IFormatProvider? provider);static member ToInt16 : obj * IFormatProvider -> int16Public Shared Function ToInt16 (value As Object, provider As IFormatProvider) As Shortパラメーター
- value
- Object
IConvertible インターフェイスを実装するオブジェクト。
- provider
- IFormatProvider
カルチャ固有の書式情報を提供するオブジェクト。
戻り値
value と等価の 16 ビット符号付き整数。value が null の場合は 0。
例外
value は Int16 型の適切な形式ではありません。
value は IConvertibleを実装していません。
value は、 Int16.MinValue より小さいか、Int16.MaxValue より大きい数値 を表します。
例
次の例では、 を実装するクラスと を実装 IConvertible するクラスを定義します IFormatProvider。 を実装する クラスのオブジェクトは、 IConvertible 値の Double 配列を保持します。 各クラスの オブジェクトが メソッドに ToInt16 渡されます。 このメソッドは、 を実装IFormatProviderする オブジェクトを使用して平均のDouble計算方法を決定し、値の配列の平均を返します。
using namespace System;
using namespace System::Collections;
// Define the types of averaging available in the class
// implementing IConvertible.
public enum class AverageType : short
{
None = 0,
GeometricMean = 1,
ArithmeticMean = 2,
Median = 3
};
// Pass an instance of this class to methods that require an
// IFormatProvider. The class instance determines the type of
// average to calculate.
ref class AverageInfo: public IFormatProvider
{
protected:
AverageType AvgType;
public:
// Specify the type of averaging in the constructor.
AverageInfo( AverageType avgType )
{
this->AvgType = avgType;
}
// This method returns a reference to the containing object
// if an object of AverageInfo type is requested.
virtual Object^ GetFormat( Type^ argType )
{
if ( argType == AverageInfo::typeid)
return this;
else
return (Object^)0;
}
property AverageType TypeOfAverage
{
// Use this property to set or get the type of averaging.
AverageType get()
{
return this->AvgType;
}
void set( AverageType value )
{
this->AvgType = value;
}
}
};
// This class encapsulates an array of double values and implements
// the IConvertible interface. Most of the IConvertible methods
// return an average of the array elements in one of three types:
// arithmetic mean, geometric mean, or median.
ref class DataSet: public IConvertible
{
private:
static Object^ null = nullptr;
protected:
ArrayList^ data;
AverageInfo^ defaultProvider;
// This method unboxes a boxed double.
double UnBoxDouble( Object^ obj )
{
return *static_cast<double^>(obj);
}
public:
// Construct the object and add an initial list of values.
// Create a default format provider.
DataSet( ... array<Double>^values )
{
data = gcnew ArrayList( (Array^)values );
defaultProvider = gcnew AverageInfo( AverageType::ArithmeticMean );
}
// Add additional values with this method.
int Add( double value )
{
data->Add( value );
return data->Count;
}
property double Item[ int ]
{
// Get, set, and add values with this indexer property.
double get( int index )
{
if ( index >= 0 && index < data->Count )
return UnBoxDouble( data[ index ] );
else
throw gcnew InvalidOperationException( "[DataSet.get] Index out of range." );
}
void set( int index, double value )
{
if ( index >= 0 && index < data->Count )
data[ index ] = value;
else
if ( index == data->Count )
data->Add( value );
else
throw gcnew InvalidOperationException( "[DataSet.set] Index out of range." );
}
}
property int Count
{
// This property returns the number of elements in the object.
int get()
{
return data->Count;
}
}
protected:
// This method calculates the average of the object's elements.
double Average( AverageType avgType )
{
double SumProd;
if ( data->Count == 0 )
return 0.0;
switch ( avgType )
{
case AverageType::GeometricMean:
SumProd = 1.0;
for ( int Index = 0; Index < data->Count; Index++ )
SumProd *= UnBoxDouble( data[ Index ] );
// This calculation will not fail with negative
// elements.
return Math::Sign( SumProd ) * Math::Pow( Math::Abs( SumProd ), 1.0 / data->Count );
case AverageType::ArithmeticMean:
SumProd = 0.0;
for ( int Index = 0; Index < data->Count; Index++ )
SumProd += UnBoxDouble( data[ Index ] );
return SumProd / data->Count;
case AverageType::Median:
if ( data->Count % 2 == 0 )
return (UnBoxDouble( data[ data->Count / 2 ] ) + UnBoxDouble( data[ data->Count / 2 - 1 ] )) / 2.0;
else
return UnBoxDouble( data[ data->Count / 2 ] );
default:
return 0.0;
}
}
// Get the AverageInfo object from the caller's format provider,
// or use the local default.
AverageInfo^ GetAverageInfo( IFormatProvider^ provider )
{
AverageInfo^ avgInfo = nullptr;
if ( provider != nullptr )
avgInfo = static_cast<AverageInfo^>(provider->GetFormat( AverageInfo::typeid ));
if ( avgInfo == nullptr )
return defaultProvider;
else
return avgInfo;
}
// Calculate the average and limit the range.
double CalcNLimitAverage( double min, double max, IFormatProvider^ provider )
{
// Get the format provider and calculate the average.
AverageInfo^ avgInfo = GetAverageInfo( provider );
double avg = Average( avgInfo->TypeOfAverage );
// Limit the range, based on the minimum and maximum values
// for the type.
return avg > max ? max : avg < min ? min : avg;
}
public:
// The following elements are required by IConvertible.
// None of these conversion functions throw exceptions. When
// the data is out of range for the type, the appropriate
// MinValue or MaxValue is used.
virtual TypeCode GetTypeCode()
{
return TypeCode::Object;
}
virtual bool ToBoolean( IFormatProvider^ provider )
{
// ToBoolean is false if the dataset is empty.
if ( data->Count <= 0 )
return false;
// For median averaging, ToBoolean is true if any
// non-discarded elements are nonzero.
else
// For median averaging, ToBoolean is true if any
// non-discarded elements are nonzero.
if ( AverageType::Median == GetAverageInfo( provider )->TypeOfAverage )
{
if ( data->Count % 2 == 0 )
return (UnBoxDouble( data[ data->Count / 2 ] ) != 0.0 || UnBoxDouble( data[ data->Count / 2 - 1 ] ) != 0.0);
else
return UnBoxDouble( data[ data->Count / 2 ] ) != 0.0;
}
// For arithmetic or geometric mean averaging, ToBoolean is
// true if any element of the dataset is nonzero.
else
{
for ( int Index = 0; Index < data->Count; Index++ )
if ( UnBoxDouble( data[ Index ] ) != 0.0 )
return true;
return false;
}
}
virtual Byte ToByte( IFormatProvider^ provider )
{
return Convert::ToByte( CalcNLimitAverage( Byte::MinValue, Byte::MaxValue, provider ) );
}
virtual Char ToChar( IFormatProvider^ provider )
{
return Convert::ToChar( Convert::ToUInt16( CalcNLimitAverage( Char::MinValue, Char::MaxValue, provider ) ) );
}
// Convert to DateTime by adding the calculated average as
// seconds to the current date and time. A valid DateTime is
// always returned.
virtual DateTime ToDateTime( IFormatProvider^ provider )
{
double seconds = Average( GetAverageInfo( provider )->TypeOfAverage );
try
{
return DateTime::Now.AddSeconds( seconds );
}
catch ( ArgumentOutOfRangeException^ )
{
return seconds < 0.0 ? DateTime::MinValue : DateTime::MaxValue;
}
}
virtual Decimal ToDecimal( IFormatProvider^ provider )
{
// The Double conversion rounds Decimal.MinValue and
// Decimal.MaxValue to invalid Decimal values, so the
// following limits must be used.
return Convert::ToDecimal( CalcNLimitAverage( -79228162514264330000000000000.0, 79228162514264330000000000000.0, provider ) );
}
virtual double ToDouble( IFormatProvider^ provider )
{
return Average( GetAverageInfo( provider )->TypeOfAverage );
}
virtual short ToInt16( IFormatProvider^ provider )
{
return Convert::ToInt16( CalcNLimitAverage( Int16::MinValue, Int16::MaxValue, provider ) );
}
virtual int ToInt32( IFormatProvider^ provider )
{
return Convert::ToInt32( CalcNLimitAverage( Int32::MinValue, Int32::MaxValue, provider ) );
}
virtual __int64 ToInt64( IFormatProvider^ provider )
{
// The Double conversion rounds Int64.MinValue and
// Int64.MaxValue to invalid Int64 values, so the following
// limits must be used.
return Convert::ToInt64( CalcNLimitAverage( -9223372036854775000, 9223372036854775000, provider ) );
}
virtual signed char ToSByte( IFormatProvider^ provider )
{
return Convert::ToSByte( CalcNLimitAverage( SByte::MinValue, SByte::MaxValue, provider ) );
}
virtual float ToSingle( IFormatProvider^ provider )
{
return Convert::ToSingle( CalcNLimitAverage( Single::MinValue, Single::MaxValue, provider ) );
}
virtual UInt16 ToUInt16( IFormatProvider^ provider )
{
return Convert::ToUInt16( CalcNLimitAverage( UInt16::MinValue, UInt16::MaxValue, provider ) );
}
virtual UInt32 ToUInt32( IFormatProvider^ provider )
{
return Convert::ToUInt32( CalcNLimitAverage( UInt32::MinValue, UInt32::MaxValue, provider ) );
}
virtual UInt64 ToUInt64( IFormatProvider^ provider )
{
// The Double conversion rounds UInt64.MaxValue to an invalid
// UInt64 value, so the following limit must be used.
return Convert::ToUInt64( CalcNLimitAverage( 0, 18446744073709550000.0, provider ) );
}
virtual Object^ ToType( Type^ conversionType, IFormatProvider^ provider )
{
return Convert::ChangeType( Average( GetAverageInfo( provider )->TypeOfAverage ), conversionType );
}
virtual String^ ToString( IFormatProvider^ provider )
{
AverageType avgType = GetAverageInfo( provider )->TypeOfAverage;
return String::Format( "( {0}: {1:G10} )", avgType, Average( avgType ) );
}
};
// Display a DataSet with three different format providers.
void DisplayDataSet( DataSet^ ds )
{
IFormatProvider^ null = nullptr;
String^ fmt = "{0,-12}{1,20}{2,20}{3,20}";
AverageInfo^ median = gcnew AverageInfo( AverageType::Median );
AverageInfo^ geMean = gcnew AverageInfo( AverageType::GeometricMean );
// Display the dataset elements.
if ( ds->Count > 0 )
{
Console::Write( "\nDataSet: [{0}", ds->Item[ 0 ] );
for ( int iX = 1; iX < ds->Count; iX++ )
Console::Write( ", {0}", ds->Item[ iX ] );
Console::WriteLine( "]\n" );
}
Console::WriteLine( fmt, "Convert::", "Default", "Geometric Mean", "Median" );
Console::WriteLine( fmt, "---------", "-------", "--------------", "------" );
Console::WriteLine( fmt, "ToBoolean", Convert::ToBoolean( ds, null ), Convert::ToBoolean( ds, geMean ), Convert::ToBoolean( ds, median ) );
Console::WriteLine( fmt, "ToByte", Convert::ToByte( ds, null ), Convert::ToByte( ds, geMean ), Convert::ToByte( ds, median ) );
Console::WriteLine( fmt, "ToChar", Convert::ToChar( ds, null ), Convert::ToChar( ds, geMean ), Convert::ToChar( ds, median ) );
Console::WriteLine( "{0,-12}{1,20:yyyy-MM-dd HH:mm:ss}"
"{2,20:yyyy-MM-dd HH:mm:ss}{3,20:yyyy-MM-dd HH:mm:ss}", "ToDateTime", Convert::ToDateTime( ds, null ), Convert::ToDateTime( ds, geMean ), Convert::ToDateTime( ds, median ) );
Console::WriteLine( fmt, "ToDecimal", Convert::ToDecimal( ds, null ), Convert::ToDecimal( ds, geMean ), Convert::ToDecimal( ds, median ) );
Console::WriteLine( fmt, "ToDouble", Convert::ToDouble( ds, null ), Convert::ToDouble( ds, geMean ), Convert::ToDouble( ds, median ) );
Console::WriteLine( fmt, "ToInt16", Convert::ToInt16( ds, null ), Convert::ToInt16( ds, geMean ), Convert::ToInt16( ds, median ) );
Console::WriteLine( fmt, "ToInt32", Convert::ToInt32( ds, null ), Convert::ToInt32( ds, geMean ), Convert::ToInt32( ds, median ) );
Console::WriteLine( fmt, "ToInt64", Convert::ToInt64( ds, null ), Convert::ToInt64( ds, geMean ), Convert::ToInt64( ds, median ) );
Console::WriteLine( fmt, "ToSByte", Convert::ToSByte( ds, null ), Convert::ToSByte( ds, geMean ), Convert::ToSByte( ds, median ) );
Console::WriteLine( fmt, "ToSingle", Convert::ToSingle( ds, null ), Convert::ToSingle( ds, geMean ), Convert::ToSingle( ds, median ) );
Console::WriteLine( fmt, "ToUInt16", Convert::ToUInt16( ds, null ), Convert::ToUInt16( ds, geMean ), Convert::ToUInt16( ds, median ) );
Console::WriteLine( fmt, "ToUInt32", Convert::ToUInt32( ds, null ), Convert::ToUInt32( ds, geMean ), Convert::ToUInt32( ds, median ) );
Console::WriteLine( fmt, "ToUInt64", Convert::ToUInt64( ds, null ), Convert::ToUInt64( ds, geMean ), Convert::ToUInt64( ds, median ) );
}
int main()
{
Console::WriteLine( "This example of the "
"Convert::To<Type>( Object*, IFormatProvider* ) methods "
"\ngenerates the following output. The example "
"displays the values \nreturned by the methods, "
"using several IFormatProvider objects.\n" );
// To call a [ParamArray] method in C++, you cannot just
// list the parameters, you need to build an array.
array<Double>^dataElem = gcnew array<Double>(6);
dataElem[ 0 ] = 10.5;
dataElem[ 1 ] = 22.2;
dataElem[ 2 ] = 45.9;
dataElem[ 3 ] = 88.7;
dataElem[ 4 ] = 156.05;
dataElem[ 5 ] = 297.6;
DataSet^ ds1 = gcnew DataSet( dataElem );
DisplayDataSet( ds1 );
dataElem = gcnew array<Double>(5);
dataElem[ 0 ] = 359999.95;
dataElem[ 1 ] = 425000;
dataElem[ 2 ] = 499999.5;
dataElem[ 3 ] = 775000;
dataElem[ 4 ] = 1695000;
DataSet^ ds2 = gcnew DataSet( dataElem );
DisplayDataSet( ds2 );
}
/*
This example of the Convert::To<Type>( Object*, IFormatProvider* ) methods
generates the following output. The example displays the values
returned by the methods, using several IFormatProvider objects.
DataSet: [10.5, 22.2, 45.9, 88.7, 156.05, 297.6]
Convert:: Default Geometric Mean Median
--------- ------- -------------- ------
ToBoolean True True True
ToByte 103 59 67
ToChar g ; C
ToDateTime 2003-05-13 15:30:23 2003-05-13 15:29:39 2003-05-13 15:29:47
ToDecimal 103.491666666667 59.4332135445164 67.3
ToDouble 103.491666666667 59.4332135445164 67.3
ToInt16 103 59 67
ToInt32 103 59 67
ToInt64 103 59 67
ToSByte 103 59 67
ToSingle 103.4917 59.43321 67.3
ToUInt16 103 59 67
ToUInt32 103 59 67
ToUInt64 103 59 67
DataSet: [359999.95, 425000, 499999.5, 775000, 1695000]
Convert:: Default Geometric Mean Median
--------- ------- -------------- ------
ToBoolean True True True
ToByte 255 255 255
ToChar ? ? ?
ToDateTime 2003-05-22 08:05:19 2003-05-20 22:54:57 2003-05-19 10:21:59
ToDecimal 750999.89 631577.237188435 499999.5
ToDouble 750999.89 631577.237188435 499999.5
ToInt16 32767 32767 32767
ToInt32 751000 631577 500000
ToInt64 751000 631577 500000
ToSByte 127 127 127
ToSingle 750999.9 631577.3 499999.5
ToUInt16 65535 65535 65535
ToUInt32 751000 631577 500000
ToUInt64 751000 631577 500000
*/
using System;
using System.Collections;
// Define the types of averaging available in the class
// implementing IConvertible.
public enum AverageType : short
{
None = 0,
GeometricMean = 1,
ArithmeticMean = 2,
Median = 3
};
// Pass an instance of this class to methods that require an
// IFormatProvider. The class instance determines the type of
// average to calculate.
public class AverageInfo : IFormatProvider
{
protected AverageType AvgType;
// Specify the type of averaging in the constructor.
public AverageInfo( AverageType avgType )
{
this.AvgType = avgType;
}
// This method returns a reference to the containing object
// if an object of AverageInfo type is requested.
public object GetFormat( Type argType )
{
if ( argType == typeof( AverageInfo ) )
return this;
else
return null;
}
// Use this property to set or get the type of averaging.
public AverageType TypeOfAverage
{
get { return this.AvgType; }
set { this.AvgType = value; }
}
}
// This class encapsulates an array of double values and implements
// the IConvertible interface. Most of the IConvertible methods
// return an average of the array elements in one of three types:
// arithmetic mean, geometric mean, or median.
public class DataSet : IConvertible
{
protected ArrayList data;
protected AverageInfo defaultProvider;
// Construct the object and add an initial list of values.
// Create a default format provider.
public DataSet( params double[ ] values )
{
data = new ArrayList( values );
defaultProvider =
new AverageInfo( AverageType.ArithmeticMean );
}
// Add additional values with this method.
public int Add( double value )
{
data.Add( value );
return data.Count;
}
// Get, set, and add values with this indexer property.
public double this[ int index ]
{
get
{
if( index >= 0 && index < data.Count )
return (double)data[ index ];
else
throw new InvalidOperationException(
"[DataSet.get] Index out of range." );
}
set
{
if( index >= 0 && index < data.Count )
data[ index ] = value;
else if( index == data.Count )
data.Add( value );
else
throw new InvalidOperationException(
"[DataSet.set] Index out of range." );
}
}
// This property returns the number of elements in the object.
public int Count
{
get { return data.Count; }
}
// This method calculates the average of the object's elements.
protected double Average( AverageType avgType )
{
double SumProd;
if( data.Count == 0 )
return 0.0;
switch( avgType )
{
case AverageType.GeometricMean:
SumProd = 1.0;
for( int Index = 0; Index < data.Count; Index++ )
SumProd *= (double)data[ Index ];
// This calculation will not fail with negative
// elements.
return Math.Sign( SumProd ) * Math.Pow(
Math.Abs( SumProd ), 1.0 / data.Count );
case AverageType.ArithmeticMean:
SumProd = 0.0;
for( int Index = 0; Index < data.Count; Index++ )
SumProd += (double)data[ Index ];
return SumProd / data.Count;
case AverageType.Median:
if( data.Count % 2 == 0 )
return ( (double)data[ data.Count / 2 ] +
(double)data[ data.Count / 2 - 1 ] ) / 2.0;
else
return (double)data[ data.Count / 2 ];
default:
return 0.0;
}
}
// Get the AverageInfo object from the caller's format provider,
// or use the local default.
protected AverageInfo GetAverageInfo( IFormatProvider provider )
{
AverageInfo avgInfo = null;
if( provider != null )
avgInfo = (AverageInfo)provider.GetFormat(
typeof( AverageInfo ) );
if ( avgInfo == null )
return defaultProvider;
else
return avgInfo;
}
// Calculate the average and limit the range.
protected double CalcNLimitAverage( double min, double max,
IFormatProvider provider )
{
// Get the format provider and calculate the average.
AverageInfo avgInfo = GetAverageInfo( provider );
double avg = Average( avgInfo.TypeOfAverage );
// Limit the range, based on the minimum and maximum values
// for the type.
return avg > max ? max : avg < min ? min : avg;
}
// The following elements are required by IConvertible.
// None of these conversion functions throw exceptions. When
// the data is out of range for the type, the appropriate
// MinValue or MaxValue is used.
public TypeCode GetTypeCode( )
{
return TypeCode.Object;
}
public bool ToBoolean( IFormatProvider provider )
{
// ToBoolean is false if the dataset is empty.
if( data.Count <= 0 )
{
return false;
}
// For median averaging, ToBoolean is true if any
// non-discarded elements are nonzero.
else if( AverageType.Median ==
GetAverageInfo( provider ).TypeOfAverage )
{
if (data.Count % 2 == 0 )
return ( (double)data[ data.Count / 2 ] != 0.0 ||
(double)data[ data.Count / 2 - 1 ] != 0.0 );
else
return (double)data[ data.Count / 2 ] != 0.0;
}
// For arithmetic or geometric mean averaging, ToBoolean is
// true if any element of the dataset is nonzero.
else
{
for( int Index = 0; Index < data.Count; Index++ )
if( (double)data[ Index ] != 0.0 )
return true;
return false;
}
}
public byte ToByte( IFormatProvider provider )
{
return Convert.ToByte( CalcNLimitAverage(
Byte.MinValue, Byte.MaxValue, provider ) );
}
public char ToChar( IFormatProvider provider )
{
return Convert.ToChar( Convert.ToUInt16( CalcNLimitAverage(
Char.MinValue, Char.MaxValue, provider ) ) );
}
// Convert to DateTime by adding the calculated average as
// seconds to the current date and time. A valid DateTime is
// always returned.
public DateTime ToDateTime( IFormatProvider provider )
{
double seconds =
Average( GetAverageInfo( provider ).TypeOfAverage );
try
{
return DateTime.Now.AddSeconds( seconds );
}
catch( ArgumentOutOfRangeException )
{
return seconds < 0.0 ? DateTime.MinValue : DateTime.MaxValue;
}
}
public decimal ToDecimal( IFormatProvider provider )
{
// The Double conversion rounds Decimal.MinValue and
// Decimal.MaxValue to invalid Decimal values, so the
// following limits must be used.
return Convert.ToDecimal( CalcNLimitAverage(
-79228162514264330000000000000.0,
79228162514264330000000000000.0, provider ) );
}
public double ToDouble( IFormatProvider provider )
{
return Average( GetAverageInfo(provider).TypeOfAverage );
}
public short ToInt16( IFormatProvider provider )
{
return Convert.ToInt16( CalcNLimitAverage(
Int16.MinValue, Int16.MaxValue, provider ) );
}
public int ToInt32( IFormatProvider provider )
{
return Convert.ToInt32( CalcNLimitAverage(
Int32.MinValue, Int32.MaxValue, provider ) );
}
public long ToInt64( IFormatProvider provider )
{
// The Double conversion rounds Int64.MinValue and
// Int64.MaxValue to invalid Int64 values, so the following
// limits must be used.
return Convert.ToInt64( CalcNLimitAverage(
-9223372036854775000, 9223372036854775000, provider ) );
}
public SByte ToSByte( IFormatProvider provider )
{
return Convert.ToSByte( CalcNLimitAverage(
SByte.MinValue, SByte.MaxValue, provider ) );
}
public float ToSingle( IFormatProvider provider )
{
return Convert.ToSingle( CalcNLimitAverage(
Single.MinValue, Single.MaxValue, provider ) );
}
public UInt16 ToUInt16( IFormatProvider provider )
{
return Convert.ToUInt16( CalcNLimitAverage(
UInt16.MinValue, UInt16.MaxValue, provider ) );
}
public UInt32 ToUInt32( IFormatProvider provider )
{
return Convert.ToUInt32( CalcNLimitAverage(
UInt32.MinValue, UInt32.MaxValue, provider ) );
}
public UInt64 ToUInt64( IFormatProvider provider )
{
// The Double conversion rounds UInt64.MaxValue to an invalid
// UInt64 value, so the following limit must be used.
return Convert.ToUInt64( CalcNLimitAverage(
0, 18446744073709550000.0, provider ) );
}
public object ToType( Type conversionType,
IFormatProvider provider )
{
return Convert.ChangeType( Average(
GetAverageInfo( provider ).TypeOfAverage ),
conversionType );
}
public string ToString( IFormatProvider provider )
{
AverageType avgType = GetAverageInfo( provider ).TypeOfAverage;
return String.Format( "( {0}: {1:G10} )", avgType,
Average( avgType ) );
}
}
class IConvertibleProviderDemo
{
// Display a DataSet with three different format providers.
public static void DisplayDataSet( DataSet ds )
{
string fmt = "{0,-12}{1,20}{2,20}{3,20}";
AverageInfo median = new AverageInfo( AverageType.Median );
AverageInfo geMean =
new AverageInfo( AverageType.GeometricMean );
// Display the dataset elements.
if( ds.Count > 0 )
{
Console.Write( "\nDataSet: [{0}", ds[ 0 ] );
for( int iX = 1; iX < ds.Count; iX++ )
Console.Write( ", {0}", ds[ iX ] );
Console.WriteLine( "]\n" );
}
Console.WriteLine( fmt, "Convert.", "Default",
"Geometric Mean", "Median");
Console.WriteLine( fmt, "--------", "-------",
"--------------", "------");
Console.WriteLine( fmt, "ToBoolean",
Convert.ToBoolean( ds, null ),
Convert.ToBoolean( ds, geMean ),
Convert.ToBoolean( ds, median ) );
Console.WriteLine( fmt, "ToByte",
Convert.ToByte( ds, null ),
Convert.ToByte( ds, geMean ),
Convert.ToByte( ds, median ) );
Console.WriteLine( fmt, "ToChar",
Convert.ToChar( ds, null ),
Convert.ToChar( ds, geMean ),
Convert.ToChar( ds, median ) );
Console.WriteLine( "{0,-12}{1,20:yyyy-MM-dd HH:mm:ss}" +
"{2,20:yyyy-MM-dd HH:mm:ss}{3,20:yyyy-MM-dd HH:mm:ss}",
"ToDateTime", Convert.ToDateTime( ds, null ),
Convert.ToDateTime( ds, geMean ),
Convert.ToDateTime( ds, median ) );
Console.WriteLine( fmt, "ToDecimal",
Convert.ToDecimal( ds, null ),
Convert.ToDecimal( ds, geMean ),
Convert.ToDecimal( ds, median ) );
Console.WriteLine( fmt, "ToDouble",
Convert.ToDouble( ds, null ),
Convert.ToDouble( ds, geMean ),
Convert.ToDouble( ds, median ) );
Console.WriteLine( fmt, "ToInt16",
Convert.ToInt16( ds, null ),
Convert.ToInt16( ds, geMean ),
Convert.ToInt16( ds, median ) );
Console.WriteLine( fmt, "ToInt32",
Convert.ToInt32( ds, null ),
Convert.ToInt32( ds, geMean ),
Convert.ToInt32( ds, median ) );
Console.WriteLine( fmt, "ToInt64",
Convert.ToInt64( ds, null ),
Convert.ToInt64( ds, geMean ),
Convert.ToInt64( ds, median ) );
Console.WriteLine( fmt, "ToSByte",
Convert.ToSByte( ds, null ),
Convert.ToSByte( ds, geMean ),
Convert.ToSByte( ds, median ) );
Console.WriteLine( fmt, "ToSingle",
Convert.ToSingle( ds, null ),
Convert.ToSingle( ds, geMean ),
Convert.ToSingle( ds, median ) );
Console.WriteLine( fmt, "ToUInt16",
Convert.ToUInt16( ds, null ),
Convert.ToUInt16( ds, geMean ),
Convert.ToUInt16( ds, median ) );
Console.WriteLine( fmt, "ToUInt32",
Convert.ToUInt32( ds, null ),
Convert.ToUInt32( ds, geMean ),
Convert.ToUInt32( ds, median ) );
Console.WriteLine( fmt, "ToUInt64",
Convert.ToUInt64( ds, null ),
Convert.ToUInt64( ds, geMean ),
Convert.ToUInt64( ds, median ) );
}
public static void Main( )
{
Console.WriteLine( "This example of " +
"the Convert.To<Type>( object, IFormatProvider ) methods " +
"\ngenerates the following output. The example " +
"displays the values \nreturned by the methods, " +
"using several IFormatProvider objects.\n" );
DataSet ds1 = new DataSet(
10.5, 22.2, 45.9, 88.7, 156.05, 297.6 );
DisplayDataSet( ds1 );
DataSet ds2 = new DataSet(
359999.95, 425000, 499999.5, 775000, 1695000 );
DisplayDataSet( ds2 );
}
}
/*
This example of the Convert.To<Type>( object, IFormatProvider ) methods
generates the following output. The example displays the values
returned by the methods, using several IFormatProvider objects.
DataSet: [10.5, 22.2, 45.9, 88.7, 156.05, 297.6]
Convert. Default Geometric Mean Median
-------- ------- -------------- ------
ToBoolean True True True
ToByte 103 59 67
ToChar g ; C
ToDateTime 2003-05-13 15:04:12 2003-05-13 15:03:28 2003-05-13 15:03:35
ToDecimal 103.491666666667 59.4332135445164 67.3
ToDouble 103.491666666667 59.4332135445164 67.3
ToInt16 103 59 67
ToInt32 103 59 67
ToInt64 103 59 67
ToSByte 103 59 67
ToSingle 103.4917 59.43321 67.3
ToUInt16 103 59 67
ToUInt32 103 59 67
ToUInt64 103 59 67
DataSet: [359999.95, 425000, 499999.5, 775000, 1695000]
Convert. Default Geometric Mean Median
-------- ------- -------------- ------
ToBoolean True True True
ToByte 255 255 255
ToChar ? ? ?
ToDateTime 2003-05-22 07:39:08 2003-05-20 22:28:45 2003-05-19 09:55:48
ToDecimal 750999.89 631577.237188435 499999.5
ToDouble 750999.89 631577.237188435 499999.5
ToInt16 32767 32767 32767
ToInt32 751000 631577 500000
ToInt64 751000 631577 500000
ToSByte 127 127 127
ToSingle 750999.9 631577.3 499999.5
ToUInt16 65535 65535 65535
ToUInt32 751000 631577 500000
ToUInt64 751000 631577 500000
*/
open System
open System.Collections
// Define the types of averaging available in the class
// implementing IConvertible.
type AverageType =
| None = 0s
| GeometricMean = 1s
| ArithmeticMean = 2s
| Median = 3s
// Pass an instance of this class to methods that require an
// IFormatProvider. The class instance determines the type of
// average to calculate.
[<AllowNullLiteral>]
type AverageInfo(avgType: AverageType) =
// Use this property to set or get the type of averaging.
member val TypeOfAverage = avgType with get, set
interface IFormatProvider with
// This method returns a reference to the containing object
// if an object of AverageInfo type is requested.
member this.GetFormat(argType: Type) =
if argType = typeof<AverageInfo> then
this
else
null
// This class encapsulates an array of double values and implements
// the IConvertible interface. Most of the IConvertible methods
// an average of the array elements in one of three types:
// arithmetic mean, geometric mean, or median.
type DataSet([<ParamArray>] values: double[]) =
let data = ResizeArray values
let defaultProvider =
AverageInfo AverageType.ArithmeticMean
// Add additional values with this method.
member _.Add(value: double) =
data.Add value
data.Count
// Get, set, and add values with this indexer property.
member _.Item
with get (index) =
if index >= 0 && index < data.Count then
data[index]
else
raise (InvalidOperationException "[DataSet.get] Index out of range.")
and set index value =
if index >= 0 && index < data.Count then
data[index] <- value
elif index = data.Count then
data.Add value
else
raise (InvalidOperationException "[DataSet.set] Index out of range.")
// This property returns the number of elements in the object.
member _.Count =
data.Count
// This method calculates the average of the object's elements.
member _.Average(avgType: AverageType) =
if data.Count = 0 then
0.0
else
match avgType with
| AverageType.GeometricMean ->
let sumProd =
Seq.reduce ( * ) data
// This calculation will not fail with negative
// elements.
(sign sumProd |> float) * Math.Pow(abs sumProd, 1.0 / (float data.Count))
| AverageType.ArithmeticMean ->
Seq.average data
| AverageType.Median ->
if data.Count % 2 = 0 then
(data[data.Count / 2] + data[data.Count / 2 - 1]) / 2.0
else
data[ data.Count / 2]
| _ ->
0.0
// Get the AverageInfo object from the caller's format provider,
// or use the local default.
member _.GetAverageInfo(provider: IFormatProvider) =
let avgInfo =
if provider <> null then
provider.GetFormat typeof<AverageInfo> :?> AverageInfo
else
null
if avgInfo = null then
defaultProvider
else
avgInfo
// Calculate the average and limit the range.
member this.CalcNLimitAverage(min: double, max: double, provider: IFormatProvider) =
// Get the format provider and calculate the average.
let avgInfo = this.GetAverageInfo provider
let avg = this.Average avgInfo.TypeOfAverage
// Limit the range, based on the minimum and maximum values
// for the type.
if avg > max then max elif avg < min then min else avg
// The following elements are required by IConvertible.
interface IConvertible with
// None of these conversion functions throw exceptions. When
// the data is out of range for the type, the appropriate
// MinValue or MaxValue is used.
member _.GetTypeCode() =
TypeCode.Object
member this.ToBoolean(provider: IFormatProvider) =
// ToBoolean is false if the dataset is empty.
if data.Count <= 0 then
false
// For median averaging, ToBoolean is true if any
// non-discarded elements are nonzero.
elif AverageType.Median = this.GetAverageInfo(provider).TypeOfAverage then
if data.Count % 2 = 0 then
(data[data.Count / 2] <> 0.0 || data[data.Count / 2 - 1] <> 0.0)
else
data[data.Count / 2] <> 0.0
// For arithmetic or geometric mean averaging, ToBoolean is
// true if any element of the dataset is nonzero.
else
Seq.exists (fun x -> x <> 0.0) data
member this.ToByte(provider: IFormatProvider) =
Convert.ToByte(this.CalcNLimitAverage(float Byte.MinValue, float Byte.MaxValue, provider) )
member this.ToChar(provider: IFormatProvider) =
Convert.ToChar(Convert.ToUInt16(this.CalcNLimitAverage(float Char.MinValue, float Char.MaxValue, provider) ) )
// Convert to DateTime by adding the calculated average as
// seconds to the current date and time. A valid DateTime is
// always returned.
member this.ToDateTime(provider: IFormatProvider) =
let seconds = this.Average(this.GetAverageInfo(provider).TypeOfAverage)
try
DateTime.Now.AddSeconds seconds
with :? ArgumentOutOfRangeException ->
if seconds < 0.0 then DateTime.MinValue else DateTime.MaxValue
member this.ToDecimal(provider: IFormatProvider) =
// The Double conversion rounds Decimal.MinValue and
// Decimal.MaxValue to invalid Decimal values, so the
// following limits must be used.
Convert.ToDecimal(this.CalcNLimitAverage(-79228162514264330000000000000.0, 79228162514264330000000000000.0, provider) )
member this.ToDouble(provider: IFormatProvider) =
this.Average(this.GetAverageInfo(provider).TypeOfAverage)
member this.ToInt16(provider: IFormatProvider) =
Convert.ToInt16(this.CalcNLimitAverage(float Int16.MinValue, float Int16.MaxValue, provider) )
member this.ToInt32(provider: IFormatProvider) =
Convert.ToInt32(this.CalcNLimitAverage(Int32.MinValue, Int32.MaxValue, provider) )
member this.ToInt64(provider: IFormatProvider) =
// The Double conversion rounds Int64.MinValue and
// Int64.MaxValue to invalid Int64 values, so the following
// limits must be used.
Convert.ToInt64(this.CalcNLimitAverage(-9223372036854775000., 9223372036854775000., provider) )
member this.ToSByte(provider: IFormatProvider) =
Convert.ToSByte(this.CalcNLimitAverage(float SByte.MinValue, float SByte.MaxValue, provider) )
member this.ToSingle(provider: IFormatProvider) =
Convert.ToSingle(this.CalcNLimitAverage(float Single.MinValue, float Single.MaxValue, provider) )
member this.ToUInt16(provider: IFormatProvider) =
Convert.ToUInt16(this.CalcNLimitAverage(float UInt16.MinValue, float UInt16.MaxValue, provider) )
member this.ToUInt32(provider: IFormatProvider) =
Convert.ToUInt32(this.CalcNLimitAverage(float UInt32.MinValue, float UInt32.MaxValue, provider) )
member this.ToUInt64(provider: IFormatProvider) =
// The Double conversion rounds UInt64.MaxValue to an invalid
// UInt64 value, so the following limit must be used.
Convert.ToUInt64(this.CalcNLimitAverage(0, 18446744073709550000.0, provider) )
member this.ToType(conversionType: Type, provider: IFormatProvider) =
Convert.ChangeType(this.Average(this.GetAverageInfo(provider).TypeOfAverage), conversionType)
member this.ToString(provider: IFormatProvider) =
let avgType = this.GetAverageInfo(provider).TypeOfAverage
$"( {avgType}: {this.Average avgType:G10} )"
// Display a DataSet with three different format providers.
let displayDataSet (ds: DataSet) =
let fmt obj1 obj2 obj3 obj4 = printfn $"{obj1,-12}{obj2,20}{obj3,20}{obj4,20}"
let median = AverageInfo AverageType.Median
let geMean =
AverageInfo AverageType.GeometricMean
// Display the dataset elements.
if ds.Count > 0 then
printf $"\nDataSet: [{ds[0]}"
for i = 1 to ds.Count - 1 do
printf $", {ds[i]}"
printfn "]\n"
fmt "Convert." "Default" "Geometric Mean" "Median"
fmt "--------" "-------" "--------------" "------"
fmt "ToBoolean"
(Convert.ToBoolean(ds, null))
(Convert.ToBoolean(ds, geMean))
(Convert.ToBoolean(ds, median))
fmt "ToByte"
(Convert.ToByte(ds, null))
(Convert.ToByte(ds, geMean))
(Convert.ToByte(ds, median))
fmt "ToChar"
(Convert.ToChar(ds, null))
(Convert.ToChar(ds, geMean))
(Convert.ToChar(ds, median))
printfn $"""{"ToDateTime",-12}{Convert.ToDateTime(ds, null).ToString "20:yyyy-MM-dd HH:mm:ss"}{Convert.ToDateTime(ds, geMean).ToString "20:yyyy-MM-dd HH:mm:ss"}{Convert.ToDateTime(ds, median).ToString "20:yyyy-MM-dd HH:mm:ss"}"""
fmt "ToDecimal"
(Convert.ToDecimal(ds, null))
(Convert.ToDecimal(ds, geMean))
(Convert.ToDecimal(ds, median))
fmt "ToDouble"
(Convert.ToDouble(ds, null))
(Convert.ToDouble(ds, geMean))
(Convert.ToDouble(ds, median))
fmt "ToInt16"
(Convert.ToInt16(ds, null))
(Convert.ToInt16(ds, geMean))
(Convert.ToInt16(ds, median))
fmt "ToInt32"
(Convert.ToInt32(ds, null))
(Convert.ToInt32(ds, geMean))
(Convert.ToInt32(ds, median))
fmt "ToInt64"
(Convert.ToInt64(ds, null))
(Convert.ToInt64(ds, geMean))
(Convert.ToInt64(ds, median))
fmt "ToSByte"
(Convert.ToSByte(ds, null))
(Convert.ToSByte(ds, geMean))
(Convert.ToSByte(ds, median))
fmt "ToSingle"
(Convert.ToSingle(ds, null))
(Convert.ToSingle(ds, geMean))
(Convert.ToSingle(ds, median))
fmt "ToUInt16"
(Convert.ToUInt16(ds, null))
(Convert.ToUInt16(ds, geMean))
(Convert.ToUInt16(ds, median))
fmt "ToUInt32"
(Convert.ToUInt32(ds, null))
(Convert.ToUInt32(ds, geMean))
(Convert.ToUInt32(ds, median))
fmt "ToUInt64"
(Convert.ToUInt64(ds, null))
(Convert.ToUInt64(ds, geMean))
(Convert.ToUInt64(ds, median))
printfn
"""This example of the Convert.To<Type>( object, IFormatprovider) methods
generates the following output. The example displays the values
returned by the methods, using several IFormatProvider objects.
"""
let ds1 = DataSet(10.5, 22.2, 45.9, 88.7, 156.05, 297.6)
displayDataSet ds1
let ds2 = DataSet(359999.95, 425000, 499999.5, 775000, 1695000)
displayDataSet ds2
// This example of the Convert.To<Type>( object, IFormatprovider) methods
// generates the following output. The example displays the values
// returned by the methods, using several IFormatProvider objects.
//
// DataSet: [10.5, 22.2, 45.9, 88.7, 156.05, 297.6]
//
// Convert. Default Geometric Mean Median
// -------- ------- -------------- ------
// ToBoolean True True True
// ToByte 103 59 67
// ToChar g ; C
// ToDateTime 2003-05-13 15:04:12 2003-05-13 15:03:28 2003-05-13 15:03:35
// ToDecimal 103.491666666667 59.4332135445164 67.3
// ToDouble 103.491666666667 59.4332135445164 67.3
// ToInt16 103 59 67
// ToInt32 103 59 67
// ToInt64 103 59 67
// ToSByte 103 59 67
// ToSingle 103.4917 59.43321 67.3
// ToUInt16 103 59 67
// ToUInt32 103 59 67
// ToUInt64 103 59 67
//
// DataSet: [359999.95, 425000, 499999.5, 775000, 1695000]
//
// Convert. Default Geometric Mean Median
// -------- ------- -------------- ------
// ToBoolean True True True
// ToByte 255 255 255
// ToChar ? ? ?
// ToDateTime 2003-05-22 07:39:08 2003-05-20 22:28:45 2003-05-19 09:55:48
// ToDecimal 750999.89 631577.237188435 499999.5
// ToDouble 750999.89 631577.237188435 499999.5
// ToInt16 32767 32767 32767
// ToInt32 751000 631577 500000
// ToInt64 751000 631577 500000
// ToSByte 127 127 127
// ToSingle 750999.9 631577.3 499999.5
// ToUInt16 65535 65535 65535
// ToUInt32 751000 631577 500000
// ToUInt64 751000 631577 500000
Imports System.Collections
Module IConvertibleProviderDemo
' Define the types of averaging available in the class
' implementing IConvertible.
Enum AverageType as Short
None = 0
GeometricMean = 1
ArithmeticMean = 2
Median = 3
End Enum
' Pass an instance of this class to methods that require an
' IFormatProvider. The class instance determines the type of
' average to calculate.
Public Class AverageInfo
Implements IFormatProvider
Protected AvgType As AverageType
' Specify the type of averaging in the constructor.
Public Sub New( avgType As AverageType )
Me.AvgType = avgType
End Sub
' This method returns a reference to the containing object
' if an object of AverageInfo type is requested.
Public Function GetFormat( argType As Type ) As Object _
Implements IFormatProvider.GetFormat
If argType Is GetType( AverageInfo ) Then
Return Me
Else
Return Nothing
End If
End Function
' Use this property to set or get the type of averaging.
Public Property TypeOfAverage( ) As AverageType
Get
Return Me.AvgType
End Get
Set( ByVal value as AverageType )
Me.AvgType = value
End Set
End Property
End Class
' This class encapsulates an array of Double values and implements
' the IConvertible interface. Most of the IConvertible methods
' return an average of the array elements in one of three types:
' arithmetic mean, geometric mean, or median.
Public Class DataSet
Implements IConvertible
Protected data As ArrayList
Protected defaultProvider As AverageInfo
' Construct the object and add an initial list of values.
' Create a default format provider.
Public Sub New( ParamArray values( ) As Double )
data = New ArrayList( values )
defaultProvider = New AverageInfo( _
AverageType.ArithmeticMean )
End Sub
' Add additional values with this method.
Public Function Add( value As Double ) As Integer
data.Add( value )
Return data.Count
End Function
' Get, set, and add values with this indexer property.
Default Public Property Item(index As Integer) As Double
Get
If index >= 0 AndAlso index < data.Count Then
Return System.Convert.ToDouble( data( index ) )
Else
Throw New InvalidOperationException( _
"[DataSet.get] Index out of range." )
End If
End Get
Set
If index >= 0 AndAlso index < data.Count Then
data( index ) = value
ElseIf index = data.Count Then
data.Add( value )
Else
Throw New InvalidOperationException( _
"[DataSet.set] Index out of range." )
End If
End Set
End Property
' This property returns the number of elements in the object.
Public ReadOnly Property Count( ) As Integer
Get
Return data.Count
End Get
End Property
' This method calculates the average of the object's elements.
Protected Function Average( ByVal avgType As AverageType ) As Double
Dim SumProd As Double
Dim Index As Integer
If data.Count = 0 Then Return 0.0
Select Case avgType
Case AverageType.GeometricMean
SumProd = 1.0
For Index = 0 To data.Count - 1
SumProd *= data( Index )
Next Index
' This calculation will not fail with negative
' elements.
Return Math.Sign( SumProd ) * Math.Pow( _
Math.Abs( SumProd ), 1.0 / data.Count )
Case AverageType.ArithmeticMean
SumProd = 0.0
For Index = 0 To data.Count - 1
SumProd += data( Index )
Next Index
Return SumProd / data.Count
Case AverageType.Median
If data.Count Mod 2 = 0 Then
Return ( data( data.Count \ 2 ) + _
data( data.Count \ 2 - 1 ) ) / 2.0
Else
Return data( data.Count \ 2 )
End If
End Select
End Function
' Get the AverageInfo object from the caller's format
' provider, or use the local default.
Protected Function GetAverageInfo( _
provider As IFormatProvider ) As AverageInfo
Dim avgInfo As AverageInfo = Nothing
If Not provider Is Nothing Then
avgInfo = provider.GetFormat( GetType( AverageInfo ) )
End If
Return IIf( avgInfo Is Nothing, defaultProvider, avgInfo )
End Function
' Calculate the average and limit the range.
Protected Function CalcNLimitAverage( min As Double, _
max As Double, provider as IFormatProvider ) As Double
' Get the format provider and calculate the average.
Dim avgInfo As AverageInfo = GetAverageInfo( provider )
Dim avg As Double = Average( avgInfo.TypeOfAverage )
' Limit the range, based on the minimum and maximum values
' for the type.
Return IIf( avg > max, max, IIf( avg < min, min, avg ) )
End Function
' The following elements are required by IConvertible.
' None of these conversion functions throw exceptions. When
' the data is out of range for the type, the appropriate
' MinValue or MaxValue is used.
Public Function GetTypeCode( ) As TypeCode _
Implements IConvertible.GetTypeCode
Return TypeCode.Object
End Function
Function ToBoolean( ByVal provider As IFormatProvider ) As _
Boolean Implements IConvertible.ToBoolean
' ToBoolean is false if the dataset is empty.
If data.Count <= 0 Then
Return False
' For median averaging, ToBoolean is true if any
' non-discarded elements are nonzero.
ElseIf AverageType.Median = _
GetAverageInfo( provider ).TypeOfAverage Then
If data.Count Mod 2 = 0 Then
Return ( data( data.Count \ 2 ) <> 0.0 Or _
data( data.Count \ 2 - 1 ) <> 0.0 )
Else
Return data( data.Count \ 2 ) <> 0.0
End If
' For arithmetic or geometric mean averaging, ToBoolean is
' true if any element of the dataset is nonzero.
Else
Dim Index As Integer
For Index = 0 To data.Count - 1
If data( Index ) <> 0.0 Then Return True
Next Index
Return False
End If
End Function
Function ToByte( ByVal provider As IFormatProvider ) As Byte _
Implements IConvertible.ToByte
Return Convert.ToByte( CalcNLimitAverage( _
Byte.MinValue, Byte.MaxValue, provider ) )
End Function
Function ToChar( ByVal provider As IFormatProvider ) As Char _
Implements IConvertible.ToChar
Return Convert.ToChar( Convert.ToUInt16( _
CalcNLimitAverage( 0.0, &HFFFF, provider ) ) )
End Function
' Convert to DateTime by adding the calculated average as
' seconds to the current date and time. A valid DateTime is
' always returned.
Function ToDateTime( ByVal provider As IFormatProvider ) As _
DateTime Implements IConvertible.ToDateTime
Dim seconds As Double = Average( _
GetAverageInfo( provider ).TypeOfAverage )
Try
Return DateTime.Now.AddSeconds( seconds )
Catch ex As ArgumentOutOfRangeException
Return IIf( seconds < 0.0, DateTime.MinValue, _
DateTime.MaxValue )
End Try
End Function
Function ToDecimal( ByVal provider As IFormatProvider ) As _
Decimal Implements IConvertible.ToDecimal
' The Double conversion rounds Decimal.MinValue and
' Decimal.MaxValue to invalid Decimal values, so the
' following limits must be used.
Return Convert.ToDecimal( CalcNLimitAverage( _
-79228162514264330000000000000.0, _
79228162514264330000000000000.0, provider ) )
End Function
Function ToDouble( ByVal provider As IFormatProvider) As _
Double Implements IConvertible.ToDouble
Return Average( GetAverageInfo( provider ).TypeOfAverage )
End Function
Function ToInt16( ByVal provider As IFormatProvider ) As _
Short Implements IConvertible.ToInt16
Return Convert.ToInt16( CalcNLimitAverage( _
Int16.MinValue, Int16.MaxValue, provider ) )
End Function
Function ToInt32( ByVal provider As IFormatProvider ) As _
Integer Implements IConvertible.ToInt32
Return Convert.ToInt32( CalcNLimitAverage( _
Int32.MinValue, Int32.MaxValue, provider ) )
End Function
Function ToInt64( ByVal provider As IFormatProvider ) As Long _
Implements IConvertible.ToInt64
' The Double conversion rounds Int64.MinValue and
' Int64.MaxValue to invalid Long values, so the following
' limits must be used.
Return Convert.ToInt64( CalcNLimitAverage( _
-9223372036854775000, 9223372036854775000, provider ) )
End Function
Function ToSByte( ByVal provider As IFormatProvider ) As _
SByte Implements IConvertible.ToSByte
' SByte.MinValue and SByte.MaxValue are not defined in
' Visual Basic.
Return Convert.ToSByte( CalcNLimitAverage( _
-128, 127, provider ) )
End Function
Function ToSingle( ByVal provider As IFormatProvider ) As _
Single Implements IConvertible.ToSingle
Return Convert.ToSingle( CalcNLimitAverage( _
Single.MinValue, Single.MaxValue, provider ) )
End Function
Function ToUInt16( ByVal provider As IFormatProvider ) As _
UInt16 Implements IConvertible.ToUInt16
' UInt16.MinValue and UInt16.MaxValue are not defined in
' Visual Basic.
Return Convert.ToUInt16( CalcNLimitAverage( _
0, &HFFFF, provider ) )
End Function
Function ToUInt32( ByVal provider As IFormatProvider ) As _
UInt32 Implements IConvertible.ToUInt32
' UInt32.MinValue and UInt32.MaxValue are not defined in
' Visual Basic.
Return Convert.ToUInt32( CalcNLimitAverage( _
0, 4294967295, provider ) )
End Function
Function ToUInt64( ByVal provider As IFormatProvider ) As _
UInt64 Implements IConvertible.ToUInt64
' UInt64.MinValue and UInt64.MaxValue are not defined in
' Visual Basic. The Double conversion would have rounded
' UInt64.MaxValue, so the following limit must be used.
Return Convert.ToUInt64( CalcNLimitAverage( _
0, 18446744073709550000.0, provider ) )
End Function
Function ToType( ByVal conversionType As Type, _
ByVal provider As IFormatProvider) As Object _
Implements IConvertible.ToType
Return Convert.ChangeType( Average( GetAverageInfo( _
provider ).TypeOfAverage ), conversionType )
End Function
Overloads Function ToString( ByVal provider As IFormatProvider _
) As String Implements IConvertible.ToString
Dim avgType as AverageType = _
GetAverageInfo( provider ).TypeOfAverage
Return String.Format( "( {0}: {1:G10} )", avgType, _
Average( avgType ) )
End Function
End Class
' Display a DataSet with three different format providers.
Sub DisplayDataSet( ds As DataSet )
Dim fmt As String = "{0,-12}{1,20}{2,20}{3,20}"
Dim median As AverageInfo = New AverageInfo( AverageType.Median )
Dim geMean As AverageInfo = _
New AverageInfo( AverageType.GeometricMean )
Dim iX As Integer
' Display the dataset elements.
If ds.Count > 0 Then
Console.Write( vbCrLf & "DataSet: [{0}", ds( 0 ) )
For iX = 1 To ds.Count - 1
Console.Write( ", {0}", ds( iX ) )
Next iX
Console.WriteLine( "]" & vbCrLf )
End If
Console.WriteLine( fmt, "Convert.", "Default", _
"Geometric Mean", "Median" )
Console.WriteLine( fmt, "--------", "-------", _
"--------------", "------" )
Console.WriteLine( fmt, "ToBoolean", _
Convert.ToBoolean( ds, Nothing ), _
Convert.ToBoolean( ds, geMean ), _
Convert.ToBoolean( ds, median ) )
Console.WriteLine( fmt, "ToByte", _
Convert.ToByte( ds, Nothing ), _
Convert.ToByte( ds, geMean ), _
Convert.ToByte( ds, median ) )
Console.WriteLine( fmt, "ToChar", _
Convert.ToChar( ds, Nothing ), _
Convert.ToChar( ds, geMean ), _
Convert.ToChar( ds, median ) )
Console.WriteLine( "{0,-12}{1,20:yyyy-MM-dd HH:mm:ss}" & _
"{2,20:yyyy-MM-dd HH:mm:ss}{3,20:yyyy-MM-dd HH:mm:ss}", _
"ToDateTime", Convert.ToDateTime( ds, Nothing ), _
Convert.ToDateTime( ds, geMean ), _
Convert.ToDateTime( ds, median ) )
Console.WriteLine( fmt, "ToDecimal", _
Convert.ToDecimal( ds, Nothing ), _
Convert.ToDecimal( ds, geMean ), _
Convert.ToDecimal( ds, median ) )
Console.WriteLine( fmt, "ToDouble", _
Convert.ToDouble( ds, Nothing ), _
Convert.ToDouble( ds, geMean ), _
Convert.ToDouble( ds, median ) )
Console.WriteLine( fmt, "ToInt16", _
Convert.ToInt16( ds, Nothing ), _
Convert.ToInt16( ds, geMean ), _
Convert.ToInt16( ds, median ) )
Console.WriteLine( fmt, "ToInt32", _
Convert.ToInt32( ds, Nothing ), _
Convert.ToInt32( ds, geMean ), _
Convert.ToInt32( ds, median ) )
Console.WriteLine( fmt, "ToInt64", _
Convert.ToInt64( ds, Nothing ), _
Convert.ToInt64( ds, geMean ), _
Convert.ToInt64( ds, median ) )
Console.WriteLine( fmt, "ToSByte", _
Convert.ToSByte( ds, Nothing ), _
Convert.ToSByte( ds, geMean ), _
Convert.ToSByte( ds, median ) )
Console.WriteLine( fmt, "ToSingle", _
Convert.ToSingle( ds, Nothing ), _
Convert.ToSingle( ds, geMean ), _
Convert.ToSingle( ds, median ) )
Console.WriteLine( fmt, "ToUInt16", _
Convert.ToUInt16( ds, Nothing ), _
Convert.ToUInt16( ds, geMean ), _
Convert.ToUInt16( ds, median ) )
Console.WriteLine( fmt, "ToUInt32", _
Convert.ToUInt32( ds, Nothing ), _
Convert.ToUInt32( ds, geMean ), _
Convert.ToUInt32( ds, median ) )
Console.WriteLine( fmt, "ToUInt64", _
Convert.ToUInt64( ds, Nothing ), _
Convert.ToUInt64( ds, geMean ), _
Convert.ToUInt64( ds, median ) )
End Sub
Sub Main( )
Console.WriteLine( _
"This example of the Convert.To<Type>( Object, " & _
"IFormatProvider ) methods " & vbCrLf & "generates " & _
"the following output. The example displays the " & _
"values " & vbCrLf & "returned by the methods, " & _
"using several IFormatProvider objects." & vbCrLf )
Dim ds1 As New DataSet( 10.5, 22.2, 45.9, 88.7, 156.05, 297.6 )
DisplayDataSet( ds1 )
Dim ds2 As New DataSet( _
359999.95, 425000, 499999.5, 775000, 1695000 )
DisplayDataSet( ds2 )
End Sub
End Module
' This example of the Convert.To<Type>( Object, IFormatProvider ) methods
' generates the following output. The example displays the values
' returned by the methods, using several IFormatProvider objects.
'
' DataSet: [10.5, 22.2, 45.9, 88.7, 156.05, 297.6]
'
' Convert. Default Geometric Mean Median
' -------- ------- -------------- ------
' ToBoolean True True True
' ToByte 103 59 67
' ToChar g ; C
' ToDateTime 2003-05-13 14:52:53 2003-05-13 14:52:09 2003-05-13 14:52:17
' ToDecimal 103.491666666667 59.4332135445164 67.3
' ToDouble 103.491666666667 59.4332135445164 67.3
' ToInt16 103 59 67
' ToInt32 103 59 67
' ToInt64 103 59 67
' ToSByte 103 59 67
' ToSingle 103.4917 59.43321 67.3
' ToUInt16 103 59 67
' ToUInt32 103 59 67
' ToUInt64 103 59 67
'
' DataSet: [359999.95, 425000, 499999.5, 775000, 1695000]
'
' Convert. Default Geometric Mean Median
' -------- ------- -------------- ------
' ToBoolean True True True
' ToByte 255 255 255
' ToChar ? ? ?
' ToDateTime 2003-05-22 07:27:49 2003-05-20 22:17:27 2003-05-19 09:44:29
' ToDecimal 750999.89 631577.237188435 499999.5
' ToDouble 750999.89 631577.237188435 499999.5
' ToInt16 32767 32767 32767
' ToInt32 751000 631577 500000
' ToInt64 751000 631577 500000
' ToSByte 127 127 127
' ToSingle 750999.9 631577.3 499999.5
' ToUInt16 65535 65535 65535
' ToUInt32 751000 631577 500000
' ToUInt64 751000 631577 500000
注釈
provider を使用すると、ユーザーは の内容に関するカルチャ固有の value変換情報を指定できます。 たとえば、 が数値を表す であるString場合value、providerその数値を表すために使用される表記に関するカルチャ固有の情報を提供できます。
基本型は無視 providerされます。ただし、 が インターフェイスを実装するユーザー定義型の場合 value は、 パラメーターを IConvertible 使用できます。
適用対象
ToInt16(UInt64)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
重要
この API は CLS 準拠ではありません。
指定した 64 ビット符号なし整数の値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::UInt64 value);[System.CLSCompliant(false)]
public static short ToInt16 (ulong value);[<System.CLSCompliant(false)>]
static member ToInt16 : uint64 -> int16Public Shared Function ToInt16 (value As ULong) As Shortパラメーター
- value
- UInt64
変換する 64 ビット符号なし整数。
戻り値
value と等価の 16 ビット符号付き整数。
- 属性
例外
value が Int16.MaxValue より大きい。
例
次の例では、符号なし長整数の配列内の各要素を 16 ビット符号付き整数に変換しようとしています。
ulong[] numbers = { UInt64.MinValue, 121, 340, UInt64.MaxValue };
short result;
foreach (ulong number in numbers)
{
try {
result = Convert.ToInt16(number);
Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.",
number.GetType().Name, number,
result.GetType().Name, result);
}
catch (OverflowException) {
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.",
number.GetType().Name, number);
}
}
// The example displays the following output:
// Converted the UInt64 value 0 to a Int16 value 0.
// Converted the UInt64 value 121 to a Int16 value 121.
// Converted the UInt64 value 340 to a Int16 value 340.
// The UInt64 value 18446744073709551615 is outside the range of the Int16 type.
let numbers =
[| UInt64.MinValue; 121uL; 340uL; UInt64.MaxValue |]
for number in numbers do
try
let result = Convert.ToInt16 number
printfn $"Converted the {number.GetType().Name} value {number} to a {result.GetType().Name} value {result}."
with :? OverflowException ->
printfn $"The {number.GetType().Name} value {number} is outside the range of the Int16 type."
// The example displays the following output:
// Converted the UInt64 value 0 to a Int16 value 0.
// Converted the UInt64 value 121 to a Int16 value 121.
// Converted the UInt64 value 340 to a Int16 value 340.
// The UInt64 value 18446744073709551615 is outside the range of the Int16 type.
Dim numbers() As ULong = { UInt64.MinValue, 121, 340, UInt64.MaxValue }
Dim result As Short
For Each number As ULong In numbers
Try
result = Convert.ToInt16(number)
Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.", _
number.GetType().Name, number, _
result.GetType().Name, result)
Catch e As OverflowException
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.", _
number.GetType().Name, number)
End Try
Next
' The example displays the following output:
' Converted the UInt64 value 0 to a Int16 value 0.
' Converted the UInt64 value 121 to a Int16 value 121.
' Converted the UInt64 value 340 to a Int16 value 340.
' The UInt64 value 18446744073709551615 is outside the range of the Int16 type.
適用対象
ToInt16(UInt32)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
重要
この API は CLS 準拠ではありません。
指定した 32 ビット符号なし整数の値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::UInt32 value);[System.CLSCompliant(false)]
public static short ToInt16 (uint value);[<System.CLSCompliant(false)>]
static member ToInt16 : uint32 -> int16Public Shared Function ToInt16 (value As UInteger) As Shortパラメーター
- value
- UInt32
変換する 32 ビット符号なし整数。
戻り値
value と等価の 16 ビット符号付き整数。
- 属性
例外
value が Int16.MaxValue より大きい。
例
次の例では、符号なし整数の配列内の各要素を 16 ビット符号付き整数に変換しようとしています。
uint[] numbers = { UInt32.MinValue, 121, 340, UInt32.MaxValue };
short result;
foreach (uint number in numbers)
{
try {
result = Convert.ToInt16(number);
Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.",
number.GetType().Name, number,
result.GetType().Name, result);
}
catch (OverflowException) {
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.",
number.GetType().Name, number);
}
}
// The example displays the following output:
// Converted the UInt32 value 0 to a Int16 value 0.
// Converted the UInt32 value 121 to a Int16 value 121.
// Converted the UInt32 value 340 to a Int16 value 340.
// The UInt32 value 4294967295 is outside the range of the Int16 type.
let numbers =
[| UInt32.MinValue; 121u; 340u; UInt32.MaxValue |]
for number in numbers do
try
let result = Convert.ToInt16 number
printfn $"Converted the {number.GetType().Name} value {number} to a {result.GetType().Name} value {result}."
with :? OverflowException ->
printfn $"The {number.GetType().Name} value {number} is outside the range of the Int16 type."
// The example displays the following output:
// Converted the UInt32 value 0 to a Int16 value 0.
// Converted the UInt32 value 121 to a Int16 value 121.
// Converted the UInt32 value 340 to a Int16 value 340.
// The UInt32 value 4294967295 is outside the range of the Int16 type.
Dim numbers() As UInteger = { UInt32.MinValue, 121, 340, UInt32.MaxValue }
Dim result As Short
For Each number As UInteger In numbers
Try
result = Convert.ToInt16(number)
Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.", _
number.GetType().Name, number, _
result.GetType().Name, result)
Catch e As OverflowException
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.", _
number.GetType().Name, number)
End Try
Next
' The example displays the following output:
' Converted the UInt32 value 0 to a Int16 value 0.
' Converted the UInt32 value 121 to a Int16 value 121.
' Converted the UInt32 value 340 to a Int16 value 340.
' The UInt32 value 4294967295 is outside the range of the Int16 type.
適用対象
ToInt16(UInt16)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
重要
この API は CLS 準拠ではありません。
指定した 16 ビット符号なし整数の値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::UInt16 value);[System.CLSCompliant(false)]
public static short ToInt16 (ushort value);[<System.CLSCompliant(false)>]
static member ToInt16 : uint16 -> int16Public Shared Function ToInt16 (value As UShort) As Shortパラメーター
- value
- UInt16
変換する 16 ビット符号なし整数。
戻り値
value と等価の 16 ビット符号付き整数。
- 属性
例外
value が Int16.MaxValue より大きい。
例
次の例では、符号なし 16 ビット整数の配列内の各要素を 16 ビット符号付き整数に変換しようとしています。
ushort[] numbers = { UInt16.MinValue, 121, 340, UInt16.MaxValue };
short result;
foreach (ushort number in numbers)
{
try {
result = Convert.ToInt16(number);
Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.",
number.GetType().Name, number,
result.GetType().Name, result);
}
catch (OverflowException) {
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.",
number.GetType().Name, number);
}
}
// The example displays the following output:
// Converted the UInt16 value 0 to a Int16 value 0.
// Converted the UInt16 value 121 to a Int16 value 121.
// Converted the UInt16 value 340 to a Int16 value 340.
// The UInt16 value 65535 is outside the range of the Int16 type.
let numbers =
[| UInt16.MinValue; 121us; 340us; UInt16.MaxValue |]
for number in numbers do
try
let result = Convert.ToInt16 number
printfn $"Converted the {number.GetType().Name} value {number} to a {result.GetType().Name} value {result}."
with :? OverflowException ->
printfn $"The {number.GetType().Name} value {number} is outside the range of the Int16 type."
// The example displays the following output:
// Converted the UInt16 value 0 to a Int16 value 0.
// Converted the UInt16 value 121 to a Int16 value 121.
// Converted the UInt16 value 340 to a Int16 value 340.
// The UInt16 value 65535 is outside the range of the Int16 type.
Dim numbers() As UShort = { UInt16.MinValue, 121, 340, UInt16.MaxValue }
Dim result As Short
For Each number As UShort In numbers
Try
result = Convert.ToInt16(number)
Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.", _
number.GetType().Name, number, _
result.GetType().Name, result)
Catch e As OverflowException
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.", _
number.GetType().Name, number)
End Try
Next
' The example displays the following output:
' Converted the UInt16 value 0 to a Int16 value 0.
' Converted the UInt16 value 121 to a Int16 value 121.
' Converted the UInt16 value 340 to a Int16 value 340.
' The UInt16 value 65535 is outside the range of the Int16 type.
適用対象
ToInt16(String)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
数値の指定した文字列形式を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::String ^ value);public static short ToInt16 (string value);public static short ToInt16 (string? value);static member ToInt16 : string -> int16Public Shared Function ToInt16 (value As String) As Shortパラメーター
- value
- String
変換する数値を含んだ文字列。
戻り値
value の数値と等価の 16 ビット符号付き整数。value が null の場合は 0 (ゼロ)。
例外
value は、オプションの符号とそれに続く数字 (0 ～ 9) のシーケンスで構成されていません。
value は、 Int16.MinValue より小さいか、Int16.MaxValue より大きい数値 を表します。
例
次の例では、既定の書式設定を使用して、 メソッドを ToInt16 使用して 16 ビット整数の文字列表現を変換します。
// Example of the Convert::ToInt16( String* ) and
// Convert::ToInt16( String*, IFormatProvider* ) methods.
using namespace System;
using namespace System::Globalization;
const __wchar_t * protoFmt = L"{0,-20}{1,-20}{2}";
// Get the exception type name; remove the namespace prefix.
String^ GetExceptionType( Exception^ ex )
{
String^ exceptionType = ex->GetType()->ToString();
return exceptionType->Substring( exceptionType->LastIndexOf( '.' ) + 1 );
}
void ConvertToInt16( String^ numericStr, IFormatProvider^ provider )
{
Object^ defaultValue;
Object^ providerValue;
// Convert numericStr to Int16 without a format provider.
try
{
defaultValue = Convert::ToInt16( numericStr );
}
catch ( Exception^ ex )
{
defaultValue = GetExceptionType( ex );
}
// Convert numericStr to Int16 with a format provider.
try
{
providerValue = Convert::ToInt16( numericStr, provider );
}
catch ( Exception^ ex )
{
providerValue = GetExceptionType( ex );
}
Console::WriteLine( gcnew String( protoFmt ), numericStr, defaultValue, providerValue );
}
int main()
{
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
NumberFormatInfo^ provider = gcnew NumberFormatInfo;
// These properties affect the conversion.
provider->NegativeSign = "neg ";
provider->PositiveSign = "pos ";
// These properties do not affect the conversion.
// The input string cannot have decimal and group separators.
provider->NumberDecimalSeparator = ".";
provider->NumberGroupSeparator = ",";
array<Int32>^sizes = {3};
provider->NumberGroupSizes = sizes;
provider->NumberNegativePattern = 0;
Console::WriteLine( "This example of\n"
" Convert::ToInt16( String* ) and \n"
" Convert::ToInt16( String*, IFormatProvider* ) "
"\ngenerates the following output. It converts "
"several strings to \nshort values, using "
"default formatting or a NumberFormatInfo object.\n" );
Console::WriteLine( gcnew String( protoFmt ), "String to convert", "Default/exception", "Provider/exception" );
Console::WriteLine( gcnew String( protoFmt ), "-----------------", "-----------------", "------------------" );
// Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider );
ConvertToInt16( "+12345", provider );
ConvertToInt16( "pos 12345", provider );
ConvertToInt16( "-12345", provider );
ConvertToInt16( "neg 12345", provider );
ConvertToInt16( "12345.", provider );
ConvertToInt16( "12,345", provider );
ConvertToInt16( "(12345)", provider );
ConvertToInt16( "32768", provider );
ConvertToInt16( "-32769", provider );
}
/*
This example of
Convert::ToInt16( String* ) and
Convert::ToInt16( String*, IFormatProvider* )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.
String to convert Default/exception Provider/exception
----------------- ----------------- ------------------
12345 12345 12345
+12345 12345 FormatException
pos 12345 FormatException 12345
-12345 -12345 FormatException
neg 12345 FormatException -12345
12345. FormatException FormatException
12,345 FormatException FormatException
(12345) FormatException FormatException
32768 OverflowException OverflowException
-32769 OverflowException FormatException
*/
// Example of the Convert.ToInt16( string ) and
// Convert.ToInt16( string, IFormatProvider ) methods.
using System;
using System.Globalization;
class ToInt16ProviderDemo
{
static string format = "{0,-20}{1,-20}{2}";
// Get the exception type name; remove the namespace prefix.
static string GetExceptionType( Exception ex )
{
string exceptionType = ex.GetType( ).ToString( );
return exceptionType.Substring(
exceptionType.LastIndexOf( '.' ) + 1 );
}
static void ConvertToInt16( string numericStr,
IFormatProvider provider )
{
object defaultValue;
object providerValue;
// Convert numericStr to Int16 without a format provider.
try
{
defaultValue = Convert.ToInt16( numericStr );
}
catch( Exception ex )
{
defaultValue = GetExceptionType( ex );
}
// Convert numericStr to Int16 with a format provider.
try
{
providerValue = Convert.ToInt16( numericStr, provider );
}
catch( Exception ex )
{
providerValue = GetExceptionType( ex );
}
Console.WriteLine( format, numericStr,
defaultValue, providerValue );
}
public static void Main( )
{
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
NumberFormatInfo provider = new NumberFormatInfo();
// These properties affect the conversion.
provider.NegativeSign = "neg ";
provider.PositiveSign = "pos ";
// These properties do not affect the conversion.
// The input string cannot have decimal and group separators.
provider.NumberDecimalSeparator = ".";
provider.NumberGroupSeparator = ",";
provider.NumberGroupSizes = new int[ ] { 3 };
provider.NumberNegativePattern = 0;
Console.WriteLine("This example of\n" +
" Convert.ToInt16( string ) and \n" +
" Convert.ToInt16( string, IFormatProvider ) " +
"\ngenerates the following output. It converts " +
"several strings to \nshort values, using " +
"default formatting or a NumberFormatInfo object.\n" );
Console.WriteLine( format, "String to convert",
"Default/exception", "Provider/exception" );
Console.WriteLine( format, "-----------------",
"-----------------", "------------------" );
// Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider );
ConvertToInt16( "+12345", provider );
ConvertToInt16( "pos 12345", provider );
ConvertToInt16( "-12345", provider );
ConvertToInt16( "neg 12345", provider );
ConvertToInt16( "12345.", provider );
ConvertToInt16( "12,345", provider );
ConvertToInt16( "(12345)", provider );
ConvertToInt16( "32768", provider );
ConvertToInt16( "-32769", provider );
}
}
/*
This example of
Convert.ToInt16( string ) and
Convert.ToInt16( string, IFormatProvider )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.
String to convert Default/exception Provider/exception
----------------- ----------------- ------------------
12345 12345 12345
+12345 12345 FormatException
pos 12345 FormatException 12345
-12345 -12345 FormatException
neg 12345 FormatException -12345
12345. FormatException FormatException
12,345 FormatException FormatException
(12345) FormatException FormatException
32768 OverflowException OverflowException
-32769 OverflowException FormatException
*/
// Example of the Convert.ToInt16( string ) and
// Convert.ToInt16( string, IFormatProvider ) methods.
open System
open System.Globalization
let format obj1 obj2 obj3 = printfn $"{obj1,-20}{obj2,-20}{obj3}"
// Get the exception type name; remove the namespace prefix.
let getExceptionType (ex: exn) =
let exceptionType = ex.GetType() |> string
exceptionType.Substring(exceptionType.LastIndexOf '.' + 1)
let convertToInt16 (numericStr: string) (provider: IFormatProvider) =
// Convert numericStr to Int16 without a format provider.
let defaultValue =
try
Convert.ToInt16 numericStr
|> string
with ex ->
getExceptionType ex
// Convert numericStr to Int16 with a format provider.
let providerValue =
try
Convert.ToInt16(numericStr, provider)
|> string
with ex ->
getExceptionType ex
format numericStr defaultValue providerValue
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
let provider = NumberFormatInfo()
// These properties affect the conversion.
provider.NegativeSign <- "neg "
provider.PositiveSign <- "pos "
// These properties do not affect the conversion.
// The input string cannot have decimal and group separators.
provider.NumberDecimalSeparator <- "."
provider.NumberGroupSeparator <- ","
provider.NumberGroupSizes <- [| 3 |]
provider.NumberNegativePattern <- 0
printfn
"""This example of
Convert.ToInt16( string ) and
Convert.ToInt16( string, IFormatProvider )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.
"""
format "String to convert" "Default/exception" "Provider/exception"
format "-----------------" "-----------------" "------------------"
// Convert strings, with and without an IFormatProvider.
convertToInt16 "12345" provider
convertToInt16 "+12345" provider
convertToInt16 "pos 12345" provider
convertToInt16 "-12345" provider
convertToInt16 "neg 12345" provider
convertToInt16 "12345." provider
convertToInt16 "12,345" provider
convertToInt16 "(12345)" provider
convertToInt16 "32768" provider
convertToInt16 "-32769" provider
// This example of
// Convert.ToInt16( string ) and
// Convert.ToInt16( string, IFormatProvider )
// generates the following output. It converts several strings to
// short values, using default formatting or a NumberFormatInfo object.
//
// String to convert Default/exception Provider/exception
// ----------------- ----------------- ------------------
// 12345 12345 12345
// +12345 12345 FormatException
// pos 12345 FormatException 12345
// -12345 -12345 FormatException
// neg 12345 FormatException -12345
// 12345. FormatException FormatException
// 12,345 FormatException FormatException
// (12345) FormatException FormatException
// 32768 OverflowException OverflowException
// -32769 OverflowException FormatException
' Example of the Convert.ToInt16( String ) and
' Convert.ToInt16( String, IFormatProvider ) methods.
Imports System.Globalization
Module ToInt16ProviderDemo
Dim format As String = "{0,-20}{1,-20}{2}"
' Get the exception type name; remove the namespace prefix.
Function GetExceptionType( ex As Exception ) As String
Dim exceptionType As String = ex.GetType( ).ToString( )
Return exceptionType.Substring( _
exceptionType.LastIndexOf( "."c ) + 1 )
End Function
Sub ConvertToInt16( numericStr As String, _
provider As IFormatProvider )
Dim defaultValue As Object
Dim providerValue As Object
' Convert numericStr to Int16 without a format provider.
Try
defaultValue = Convert.ToInt16( numericStr )
Catch ex As Exception
defaultValue = GetExceptionType( ex )
End Try
' Convert numericStr to Int16 with a format provider.
Try
providerValue = Convert.ToInt16( numericStr, provider )
Catch ex As Exception
providerValue = GetExceptionType( ex )
End Try
Console.WriteLine( format, numericStr, _
defaultValue, providerValue )
End Sub
Sub Main( )
' Create a NumberFormatInfo object and set several of its
' properties that apply to numbers.
Dim provider As NumberFormatInfo = new NumberFormatInfo( )
' These properties affect the conversion.
provider.NegativeSign = "neg "
provider.PositiveSign = "pos "
' These properties do not affect the conversion.
' The input string cannot have decimal and group separators.
provider.NumberDecimalSeparator = "."
provider.NumberGroupSeparator = ","
provider.NumberGroupSizes = New Integer( ) { 3 }
provider.NumberNegativePattern = 0
Console.WriteLine( "This example of" & vbCrLf & _
" Convert.ToInt16( String ) and " & vbCrLf & _
" Convert.ToInt16( String, IFormatProvider ) " & _
vbCrLf & "generates the following output. It " & _
"converts several strings to " & vbCrLf & "Short " & _
"values, using default formatting " & _
"or a NumberFormatInfo object." & vbCrLf )
Console.WriteLine( format, "String to convert", _
"Default/exception", "Provider/exception" )
Console.WriteLine( format, "-----------------", _
"-----------------", "------------------" )
' Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider )
ConvertToInt16( "+12345", provider )
ConvertToInt16( "pos 12345", provider )
ConvertToInt16( "-12345", provider )
ConvertToInt16( "neg 12345", provider )
ConvertToInt16( "12345.", provider )
ConvertToInt16( "12,345", provider )
ConvertToInt16( "(12345)", provider )
ConvertToInt16( "32768", provider )
ConvertToInt16( "-32769", provider )
End Sub
End Module
' This example of
' Convert.ToInt16( String ) and
' Convert.ToInt16( String, IFormatProvider )
' generates the following output. It converts several strings to
' Short values, using default formatting or a NumberFormatInfo object.
'
' String to convert Default/exception Provider/exception
' ----------------- ----------------- ------------------
' 12345 12345 12345
' +12345 12345 FormatException
' pos 12345 FormatException 12345
' -12345 -12345 FormatException
' neg 12345 FormatException -12345
' 12345. FormatException FormatException
' 12,345 FormatException FormatException
' (12345) FormatException FormatException
' 32768 OverflowException OverflowException
' -32769 OverflowException FormatException
注釈
メソッドの ToInt16(String) 使用は、 メソッドに渡すこと value と Int16.Parse(String) 同じです。
value は、現在のカルチャの書式設定規則を使用して解釈されます。
変換が失敗した場合に例外を処理しない場合は、代わりに メソッドを Int16.TryParse 呼び出すことができます。 変換が Boolean 成功したか失敗したかを示す値を返します。
こちらもご覧ください
適用対象
ToInt16(String, Int32)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定した基数での数値の文字列形式を、等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::String ^ value, int fromBase);public static short ToInt16 (string value, int fromBase);public static short ToInt16 (string? value, int fromBase);static member ToInt16 : string * int -> int16Public Shared Function ToInt16 (value As String, fromBase As Integer) As Shortパラメーター
- value
- String
変換する数値を含んだ文字列。
- fromBase
- Int32
value 内の数値の基数。これは 2、8、10、または 16 である必要があります。
戻り値
value の数値と等価の 16 ビット符号付き整数。value が null の場合は 0 (ゼロ)。
例外
value が Emptyです。
value に、fromBase で指定された進法では使用できない数字である文字が含まれています。
value 内の最初の文字が正しくない場合は、例外メッセージは、変換する数字がないことを示します。それ以外の場合は、このメッセージは、value に正しくない末尾文字が含まれていることを示します。
valueは 10 進法でない符号付き数値を表しますが、前に負の符号が付いています。
または
value は、 Int16.MinValue より小さいか、Int16.MaxValue より大きい数値 を表します。
例
次の例では、文字列配列内の各要素を 16 進数の文字列として解釈し、それを 16 ビット符号付き整数に変換しようとします。
using System;
public class Example
{
public static void Main()
{
string[] hexStrings = { "8000", "0FFF", "f000", "00A30", "D", "-13",
"9AC61", "GAD" };
foreach (string hexString in hexStrings)
{
try {
short number = Convert.ToInt16(hexString, 16);
Console.WriteLine("Converted '{0}' to {1:N0}.", hexString, number);
}
catch (FormatException) {
Console.WriteLine("'{0}' is not in the correct format for a hexadecimal number.",
hexString);
}
catch (OverflowException) {
Console.WriteLine("'{0}' is outside the range of an Int16.", hexString);
}
catch (ArgumentException) {
Console.WriteLine("'{0}' is invalid in base 16.", hexString);
}
}
}
}
// The example displays the following output:
// Converted '8000' to -32,768.
// Converted '0FFF' to 4,095.
// Converted 'f000' to -4,096.
// Converted '00A30' to 2,608.
// Converted 'D' to 13.
// '-13' is invalid in base 16.
// '9AC61' is outside the range of an Int16.
// 'GAD' is not in the correct format for a hexadecimal number.
open System
let hexStrings =
[| "8000"; "0FFF"; "f000"; "00A30"
"D"; "-13"; "9AC61"; "GAD" |]
for hexString in hexStrings do
try
let number = Convert.ToInt16(hexString, 16)
printfn $"Converted '{hexString}' to {number:N0}."
with
| :? FormatException ->
printfn $"'{hexString}' is not in the correct format for a hexadecimal number."
| :? OverflowException ->
printfn $"'{hexString}' is outside the range of an Int16."
| :? ArgumentException ->
printfn $"'{hexString}' is invalid in base 16."
// The example displays the following output:
// Converted '8000' to -32,768.
// Converted '0FFF' to 4,095.
// Converted 'f000' to -4,096.
// Converted '00A30' to 2,608.
// Converted 'D' to 13.
// '-13' is invalid in base 16.
// '9AC61' is outside the range of an Int16.
// 'GAD' is not in the correct format for a hexadecimal number.
Module Example
Public Sub Main()
Dim hexStrings() As String = { "8000", "0FFF", "f000", "00A30", "D", _
"-13", "9AC61", "GAD" }
For Each hexString As String In hexStrings
Try
Dim number As Short = Convert.ToInt16(hexString, 16)
Console.WriteLine("Converted '{0}' to {1:N0}.", hexString, number)
Catch e As FormatException
Console.WriteLine("'{0}' is not in the correct format for a hexadecimal number.", _
hexString)
Catch e As OverflowException
Console.WriteLine("'{0}' is outside the range of an Int16.", hexString)
Catch e As ArgumentException
Console.WriteLine("'{0}' is invalid in base 16.", hexString)
End Try
Next
End Sub
End Module
' The example displays the following output:
' Converted '8000' to -32,768.
' Converted '0FFF' to 4,095.
' Converted 'f000' to -4,096.
' Converted '00A30' to 2,608.
' Converted 'D' to 13.
' '-13' is invalid in base 16.
' '9AC61' is outside the range of an Int16.
' 'GAD' is not in the correct format for a hexadecimal number.
注釈
が 16 の場合 fromBase は、パラメーターで指定された数値の前に value "0x" または "0X" を付けることができます。
負の符号は 10 の数値以外の表現ではサポートされていないため、 メソッドは負の ToInt16(String, Int32) 数値が 2 の補数表現を使用することを前提としています。 つまり、 メソッドは常に整数の最上位バイナリ ビット (ビット 15) を符号ビットとして解釈します。 その結果、データ型の範囲外 Int16 の 10 以外の数値が、メソッドが例外をスローせずに値に Int16 変換されるコードを記述できます。 次の例では、1 ずつインクリメント Int16.MaxValue し、結果の数値を 16 進数の文字列表現に変換してから、 メソッドを ToInt16(String, Int32) 呼び出します。 メソッドは例外をスローする代わりに、"0x8000 -32768 に変換します" というメッセージを表示します。
// Create a hexadecimal value out of range of the Int16 type.
string value = Convert.ToString((int) short.MaxValue + 1, 16);
// Convert it back to a number.
try
{
short number = Convert.ToInt16(value, 16);
Console.WriteLine("0x{0} converts to {1}.", value, number);
}
catch (OverflowException)
{
Console.WriteLine("Unable to convert '0x{0}' to a 16-bit integer.", value);
}
// Create a hexadecimal value out of range of the Int16 type.
let value = Convert.ToString(int Int16.MaxValue + 1, 16)
// Convert it back to a number.
try
let number = Convert.ToInt16(value, 16)
printfn $"0x{value} converts to {number}."
with :? OverflowException ->
printfn $"Unable to convert '0x{value}' to a 16-bit integer."
' Create a hexadecimal value out of range of the Int16 type.
Dim value As String = Convert.ToString(CInt(Short.MaxValue) + 1, 16)
' Convert it back to a number.
Try
Dim number As Short = Convert.ToInt16(value, 16)
Console.WriteLine("0x{0} converts to {1}.", value, number)
Catch e As OverflowException
Console.WriteLine("Unable to convert '0x{0}' to a 16-bit integer.", value)
End Try
バイナリ演算または数値変換を実行するときは、常に開発者が、メソッドが適切な数値表現を使用して特定の値を解釈していることを確認する必要があります。 次の例に示すように、数値の符号を取得してから 16 進数の文字列表現に変換することで、メソッドが適切にオーバーフローを処理するようにすることができます。 元の値が正の場合は例外をスローしますが、整数に戻すと負の値が返されます。
// Create a hexadecimal value out of range of the Short type.
int sourceNumber = (int) short.MaxValue + 1;
bool isNegative = (Math.Sign(sourceNumber) == -1);
string value = Convert.ToString(sourceNumber, 16);
short targetNumber;
try
{
targetNumber = Convert.ToInt16(value, 16);
if (! isNegative && ((targetNumber & 0x8000) != 0))
throw new OverflowException();
else
Console.WriteLine("0x{0} converts to {1}.", value, targetNumber);
}
catch (OverflowException)
{
Console.WriteLine("Unable to convert '0x{0}' to a 16-bit integer.", value);
}
// Displays the following to the console:
// Unable to convert '0x8000' to a 16-bit integer.
// Create a hexadecimal value out of range of the Short type.
let sourceNumber = int Int16.MaxValue + 1
let isNegative = sign sourceNumber = -1
let value = Convert.ToString(sourceNumber, 16)
try
let targetNumber = Convert.ToInt16(value, 16)
if not isNegative && targetNumber &&& 0x8000s <> 0s then
raise (OverflowException())
else
printfn $"0x{value} converts to {targetNumber}."
with :? OverflowException ->
printfn $"Unable to convert '0x{value}' to a 16-bit integer."
// Displays the following to the console:
// Unable to convert '0x8000' to a 16-bit integer.
' Create a hexadecimal value out of range of the Short type.
Dim sourceNumber As Integer = CInt(Short.MaxValue) + 1
Dim isNegative As Boolean = (Math.Sign(sourceNumber) = -1)
Dim value As String = Convert.ToString(sourceNumber, 16)
Dim targetNumber As Short
Try
targetNumber = Convert.ToInt16(value, 16)
If Not isNegative And ((targetNumber And &H8000) <> 0) Then
Throw New OverflowException()
Else
Console.WriteLine("0x{0} converts to {1}.", value, targetNumber)
End If
Catch e As OverflowException
Console.WriteLine("Unable to convert '0x{0}' to a 16-bit integer.", value)
End Try
' Displays the following to the console:
' Unable to convert '0x8000' to a 16-bit integer.
適用対象
ToInt16(SByte)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
重要
この API は CLS 準拠ではありません。
指定した 8 ビット符号付き整数の値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::SByte value);[System.CLSCompliant(false)]
public static short ToInt16 (sbyte value);[<System.CLSCompliant(false)>]
static member ToInt16 : sbyte -> int16Public Shared Function ToInt16 (value As SByte) As Shortパラメーター
- value
- SByte
変換する 8 ビット符号付き整数。
戻り値
value と等価の 8 ビット符号付き整数。
- 属性
例
次の例では、符号付きバイトの配列内の各要素を 16 ビット符号付き整数に変換します。
sbyte[] numbers = { SByte.MinValue, -1, 0, 10, SByte.MaxValue };
short result;
foreach (sbyte number in numbers)
{
result = Convert.ToInt16(number);
Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
number.GetType().Name, number,
result.GetType().Name, result);
}
// The example displays the following output:
// Converted the SByte value -128 to the Int16 value -128.
// Converted the SByte value -1 to the Int16 value -1.
// Converted the SByte value 0 to the Int16 value 0.
// Converted the SByte value 10 to the Int16 value 10.
// Converted the SByte value 127 to the Int16 value 127.
let numbers =
[| SByte.MinValue; -1y; 0y; 10y; SByte.MaxValue |]
for number in numbers do
let result = Convert.ToInt16 number
printfn $"Converted the {number.GetType().Name} value {number} to the {result.GetType().Name} value {result}."
// The example displays the following output:
// Converted the SByte value -128 to the Int16 value -128.
// Converted the SByte value -1 to the Int16 value -1.
// Converted the SByte value 0 to the Int16 value 0.
// Converted the SByte value 10 to the Int16 value 10.
// Converted the SByte value 127 to the Int16 value 127.
Dim numbers() As SByte = { SByte.MinValue, -1, 0, 10, SByte.MaxValue }
Dim result As Short
For Each number As SByte In numbers
result = Convert.ToInt16(number)
Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
number.GetType().Name, number, _
result.GetType().Name, result)
Next
' The example displays the following output:
' Converted the SByte value -128 to the Int16 value -128.
' Converted the SByte value -1 to the Int16 value -1.
' Converted the SByte value 0 to the Int16 value 0.
' Converted the SByte value 10 to the Int16 value 10.
' Converted the SByte value 127 to the Int16 value 127.
適用対象
ToInt16(Int16)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定した 16 ビット符号付き整数が返されます。実際の変換は行われません。
public:
static short ToInt16(short value);public static short ToInt16 (short value);static member ToInt16 : int16 -> int16Public Shared Function ToInt16 (value As Short) As Shortパラメーター
- value
- Int16
返される 16 ビット符号付き整数。
戻り値
value は変更されずに返されます。
適用対象
ToInt16(Int64)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定された 64 ビット符号付き整数の値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(long value);public static short ToInt16 (long value);static member ToInt16 : int64 -> int16Public Shared Function ToInt16 (value As Long) As Shortパラメーター
- value
- Int64
変換する 64 ビット符号付き整数。
戻り値
value と等価の 16 ビット符号付き整数。
例外
value が Int16.MaxValue より大きいか、 Int16.MinValue より小さい。
例
次の例では、長整数の配列内の各要素を 16 ビット符号付き整数に変換しようとしています。
long[] numbers = { Int64.MinValue, -1, 0, 121, 340, Int64.MaxValue };
short result;
foreach (long number in numbers)
{
try {
result = Convert.ToInt16(number);
Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
number.GetType().Name, number,
result.GetType().Name, result);
}
catch (OverflowException) {
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.",
number.GetType().Name, number);
}
}
// The example displays the following output:
// The Int64 value -9223372036854775808 is outside the range of the Int16 type.
// Converted the Int64 value -1 to the Int16 value -1.
// Converted the Int64 value 0 to the Int16 value 0.
// Converted the Int64 value 121 to the Int16 value 121.
// Converted the Int64 value 340 to the Int16 value 340.
// The Int64 value 9223372036854775807 is outside the range of the Int16 type.
let numbers =
[| Int64.MinValue; -1; 0; 121; 340; Int64.MaxValue |]
for number in numbers do
try
let result = Convert.ToInt16 number
printfn $"Converted the {number.GetType().Name} value {number} to the {result.GetType().Name} value {result}."
with :? OverflowException ->
printfn $"The {number.GetType().Name} value {number} is outside the range of the Int16 type."
// The example displays the following output:
// The Int64 value -9223372036854775808 is outside the range of the Int16 type.
// Converted the Int64 value -1 to the Int16 value -1.
// Converted the Int64 value 0 to the Int16 value 0.
// Converted the Int64 value 121 to the Int16 value 121.
// Converted the Int64 value 340 to the Int16 value 340.
// The Int64 value 9223372036854775807 is outside the range of the Int16 type.
Dim numbers() As Long = { Int64.MinValue, -1, 0, 121, 340, Int64.MaxValue }
Dim result As Short
For Each number As Long In numbers
Try
result = Convert.ToInt16(number)
Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
number.GetType().Name, number, _
result.GetType().Name, result)
Catch e As OverflowException
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.", _
number.GetType().Name, number)
End Try
Next
' The example displays the following output:
' The Int64 value -9223372036854775808 is outside the range of the Int16 type.
' Converted the Int64 value -1 to the Int16 value -1.
' Converted the Int64 value 0 to the Int16 value 0.
' Converted the Int64 value 121 to the Int16 value 121.
' Converted the Int64 value 340 to the Int16 value 340.
' The Int64 value 9223372036854775807 is outside the range of the Int16 type.
適用対象
ToInt16(Int32)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定した 32 ビット符号付き整数の値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(int value);public static short ToInt16 (int value);static member ToInt16 : int -> int16Public Shared Function ToInt16 (value As Integer) As Shortパラメーター
- value
- Int32
変換する 32 ビット符号付き整数。
戻り値
value と等価の 16 ビット符号付き整数。
例外
value が Int16.MaxValue より大きいか、 Int16.MinValue より小さい。
例
次の例では、整数の配列内の各要素を 16 ビット符号付き整数に変換しようとしています。
int[] numbers = { Int32.MinValue, -1, 0, 121, 340, Int32.MaxValue };
short result;
foreach (int number in numbers)
{
try {
result = Convert.ToInt16(number);
Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.",
number.GetType().Name, number,
result.GetType().Name, result);
}
catch (OverflowException) {
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.",
number.GetType().Name, number);
}
}
// The example displays the following output:
// The Int32 value -2147483648 is outside the range of the Int16 type.
// Converted the Int32 value -1 to a Int16 value -1.
// Converted the Int32 value 0 to a Int16 value 0.
// Converted the Int32 value 121 to a Int16 value 121.
// Converted the Int32 value 340 to a Int16 value 340.
// The Int32 value 2147483647 is outside the range of the Int16 type.
let numbers =
[| Int32.MinValue; -1; 0; 121; 340; Int32.MaxValue |]
for number in numbers do
try
let result = Convert.ToInt16 number
printfn $"Converted the {number.GetType().Name} value {number} to a {result.GetType().Name} value {result}."
with :? OverflowException ->
printfn $"The {number.GetType().Name} value {number} is outside the range of the Int16 type."
// The example displays the following output:
// The Int32 value -2147483648 is outside the range of the Int16 type.
// Converted the Int32 value -1 to a Int16 value -1.
// Converted the Int32 value 0 to a Int16 value 0.
// Converted the Int32 value 121 to a Int16 value 121.
// Converted the Int32 value 340 to a Int16 value 340.
// The Int32 value 2147483647 is outside the range of the Int16 type.
Dim numbers() As Integer = { Int32.MinValue, -1, 0, 121, 340, Int32.MaxValue }
Dim result As Short
For Each number As Integer In numbers
Try
result = Convert.ToInt16(number)
Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.", _
number.GetType().Name, number, _
result.GetType().Name, result)
Catch e As OverflowException
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.", _
number.GetType().Name, number)
End Try
Next
' The example displays the following output:
' The Int32 value -2147483648 is outside the range of the Int16 type.
' Converted the Int32 value -1 to a Int16 value -1.
' Converted the Int32 value 0 to a Int16 value 0.
' Converted the Int32 value 121 to a Int16 value 121.
' Converted the Int32 value 340 to a Int16 value 340.
' The Int32 value 2147483647 is outside the range of the Int16 type.
適用対象
ToInt16(Double)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定された倍精度浮動小数点数値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(double value);public static short ToInt16 (double value);static member ToInt16 : double -> int16Public Shared Function ToInt16 (value As Double) As Shortパラメーター
- value
- Double
変換する倍精度浮動小数点数。
戻り値
近似値の 16 ビット符号付き整数に丸められた value。
value が 2 つの整数のちょうど中間にある場合は、偶数が返されます。つまり、4.5 は 4 に変換され、5.5 は 6 に変換されます。
例外
value が Int16.MaxValue より大きいか、 Int16.MinValue より小さい。
例
次の例では、値の配列内の Double 各要素を 16 ビット符号付き整数に変換します。 この例は、変換を実行する前に、 Double 値の小数部が丸められることを示しています。
double[] values = { Double.MinValue, -1.38e10, -1023.299, -12.98,
0, 9.113e-16, 103.919, 17834.191, Double.MaxValue };
short result;
foreach (double value in values)
{
try {
result = Convert.ToInt16(value);
Console.WriteLine("Converted {0} to {1}.", value, result);
}
catch (OverflowException)
{
Console.WriteLine("{0} is outside the range of the Int16 type.", value);
}
}
// -1.79769313486232E+308 is outside the range of the Int16 type.
// -13800000000 is outside the range of the Int16 type.
// Converted -1023.299 to -1023.
// Converted -12.98 to -13.
// Converted 0 to 0.
// Converted 9.113E-16 to 0.
// Converted 103.919 to 104.
// Converted 17834.191 to 17834.
// 1.79769313486232E+308 is outside the range of the Int16 type.
let values =
[| Double.MinValue; -1.38e10; -1023.299; -12.98
0; 9.113e-16; 103.919; 17834.191; Double.MaxValue |]
for value in values do
try
let result = Convert.ToInt16 value
printfn $"Converted {value} to {result}."
with :? OverflowException ->
printfn $"{value} is outside the range of the Int16 type."
// -1.79769313486232E+308 is outside the range of the Int16 type.
// -13800000000 is outside the range of the Int16 type.
// Converted -1023.299 to -1023.
// Converted -12.98 to -13.
// Converted 0 to 0.
// Converted 9.113E-16 to 0.
// Converted 103.919 to 104.
// Converted 17834.191 to 17834.
// 1.79769313486232E+308 is outside the range of the Int16 type.
Dim values() As Double = { Double.MinValue, -1.38e10, -1023.299, -12.98, _
0, 9.113e-16, 103.919, 17834.191, Double.MaxValue }
Dim result As Short
For Each value As Double In values
Try
result = Convert.ToInt16(value)
Console.WriteLine("Converted {0} to {1}.", value, result)
Catch e As OverflowException
Console.WriteLine("{0} is outside the range of the Int16 type.", value)
End Try
Next
' -1.79769313486232E+308 is outside the range of the Int16 type.
' -13800000000 is outside the range of the Int16 type.
' Converted -1023.299 to -1023.
' Converted -12.98 to -13.
' Converted 0 to 0.
' Converted 9.113E-16 to 0.
' Converted 103.919 to 104.
' Converted 17834.191 to 17834.
' 1.79769313486232E+308 is outside the range of the Int16 type.
こちらもご覧ください
適用対象
ToInt16(Decimal)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定した 10 進数値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::Decimal value);public static short ToInt16 (decimal value);static member ToInt16 : decimal -> int16Public Shared Function ToInt16 (value As Decimal) As Shortパラメーター
- value
- Decimal
変換する 10 進数。
戻り値
近似値の 16 ビット符号付き整数に丸められた value。
value が 2 つの整数のちょうど中間にある場合は、偶数が返されます。つまり、4.5 は 4 に変換され、5.5 は 6 に変換されます。
例外
value が Int16.MaxValue より大きいか、 Int16.MinValue より小さい。
例
次の例では、値の配列内の Decimal 各要素を 16 ビット符号付き整数に変換しようとしています。 この例は、変換の実行時に Decimal 値の小数部が丸められることを示しています。
decimal[] values = { Decimal.MinValue, -1034.23m, -12m, 0m, 147m,
9214.16m, Decimal.MaxValue };
short result;
foreach (decimal value in values)
{
try {
result = Convert.ToInt16(value);
Console.WriteLine("Converted {0} to {1}.", value, result);
}
catch (OverflowException)
{
Console.WriteLine("{0} is outside the range of the Int16 type.",
value);
}
}
// The example displays the following output:
// -79228162514264337593543950335 is outside the range of the Int16 type.
// Converted -1034.23 to -1034.
// Converted -12 to -12.
// Converted 0 to 0.
// Converted 147 to 147.
// Converted 9214.16 to 9214.
// 79228162514264337593543950335 is outside the range of the Int16 type.
let values =
[| Decimal.MinValue; -1034.23m; -12m; 0m
147m; 9214.16m; Decimal.MaxValue |]
for value in values do
try
let result = Convert.ToInt16 value
printfn $"Converted {value} to {result}."
with :? OverflowException ->
printfn $"{value} is outside the range of the Int16 type."
// The example displays the following output:
// -79228162514264337593543950335 is outside the range of the Int16 type.
// Converted -1034.23 to -1034.
// Converted -12 to -12.
// Converted 0 to 0.
// Converted 147 to 147.
// Converted 9214.16 to 9214.
// 79228162514264337593543950335 is outside the range of the Int16 type.
Dim values() As Decimal = { Decimal.MinValue, -1034.23d, -12d, 0d, 147d, _
9214.16d, Decimal.MaxValue }
Dim result As Short
For Each value As Decimal In values
Try
result = Convert.ToInt16(value)
Console.WriteLine("Converted {0} to {1}.", value, result)
Catch e As OverflowException
Console.WriteLine("{0} is outside the range of the Int16 type.", _
value)
End Try
Next
' The example displays the following output:
' -79228162514264337593543950335 is outside the range of the Int16 type.
' Converted -1034.23 to -1034.
' Converted -12 to -12.
' Converted 0 to 0.
' Converted 147 to 147.
' Converted 9214.16 to 9214.
' 79228162514264337593543950335 is outside the range of the Int16 type.
こちらもご覧ください
適用対象
ToInt16(DateTime)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
このメソッドを呼び出すと、必ず InvalidCastException がスローされます。
public:
static short ToInt16(DateTime value);public static short ToInt16 (DateTime value);static member ToInt16 : DateTime -> int16Public Shared Function ToInt16 (value As DateTime) As Shortパラメーター
- value
- DateTime
変換する日時の値。
戻り値
この変換はサポートされていません。 値は返されません。
例外
この変換はサポートされていません。
適用対象
ToInt16(Char)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定した Unicode 文字の値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(char value);public static short ToInt16 (char value);static member ToInt16 : char -> int16Public Shared Function ToInt16 (value As Char) As Shortパラメーター
- value
- Char
変換する Unicode 文字。
戻り値
value と等価の 16 ビット符号付き整数。
例外
value が Int16.MaxValue より大きい。
例
次の例では、値の配列内の Char 各要素を 16 ビット符号付き整数に変換しようとしています。
char[] chars = { 'a', 'z', '\x0007', '\x03FF',
'\x7FFF', '\xFFFE' };
short result;
foreach (char ch in chars)
{
try {
result = Convert.ToInt16(ch);
Console.WriteLine("'{0}' converts to {1}.", ch, result);
}
catch (OverflowException) {
Console.WriteLine("Unable to convert u+{0} to an Int16.",
((int)ch).ToString("X4"));
}
}
// The example displays the following output:
// 'a' converts to 97.
// 'z' converts to 122.
// '' converts to 7.
// 'Ͽ' converts to 1023.
// '翿' converts to 32767.
// Unable to convert u+FFFE to an Int16.
let chars =
[| 'a'; 'z'; '\u0007'; '\u03FF'; '\u7FFF'; '\uFFFE' |]
for ch in chars do
try
let result = Convert.ToInt16 ch
printfn $"'{ch}' converts to {result}."
with :? OverflowException ->
printfn $"Unable to convert u+{int ch:X4} to an Int16."
// The example displays the following output:
// 'a' converts to 97.
// 'z' converts to 122.
// '' converts to 7.
// 'Ͽ' converts to 1023.
// '翿' converts to 32767.
// Unable to convert u+FFFE to an Int16.
Dim chars() As Char = { "a"c, "z"c, ChrW(7), ChrW(1023), _
ChrW(Short.MaxValue), ChrW(&hFFFE) }
Dim result As Short
For Each ch As Char in chars
Try
result = Convert.ToInt16(ch)
Console.WriteLine("'{0}' converts to {1}.", ch, result)
Catch e As OverflowException
Console.WriteLine("Unable to convert u+{0} to an Int16.", _
AscW(ch).ToString("X4"))
End Try
Next
' The example displays the following output:
' 'a' converts to 97.
' 'z' converts to 122.
' '' converts to 7.
' 'Ͽ' converts to 1023.
' '翿' converts to 32767.
' Unable to convert u+FFFE to an Int16.
適用対象
ToInt16(Byte)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定した 8 ビット符号なし整数の値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::Byte value);public static short ToInt16 (byte value);static member ToInt16 : byte -> int16Public Shared Function ToInt16 (value As Byte) As Shortパラメーター
- value
- Byte
変換する 8 ビット符号なし整数。
戻り値
value と等価の 16 ビット符号付き整数。
例
次の例では、値の配列内の Byte 各要素を 16 ビット符号付き整数に変換します。
byte[] bytes = { Byte.MinValue, 14, 122, Byte.MaxValue};
short result;
foreach (byte byteValue in bytes)
{
result = Convert.ToInt16(byteValue);
Console.WriteLine("The Byte value {0} converts to {1}.",
byteValue, result);
}
// The example displays the following output:
// The Byte value 0 converts to 0.
// The Byte value 14 converts to 14.
// The Byte value 122 converts to 122.
// The Byte value 255 converts to 255.
let bytes = [| Byte.MinValue; 14uy; 122uy; Byte.MaxValue |]
for byteValue in bytes do
let result = Convert.ToInt16 byteValue
printfn $"The Byte value {byteValue} converts to {result}."
// The example displays the following output:
// The Byte value 0 converts to 0.
// The Byte value 14 converts to 14.
// The Byte value 122 converts to 122.
// The Byte value 255 converts to 255.
Dim bytes() As Byte = { Byte.MinValue, 14, 122, Byte.MaxValue}
Dim result As Short
For Each byteValue As Byte In bytes
result = Convert.ToInt16(byteValue)
Console.WriteLine("The Byte value {0} converts to {1}.", _
byteValue, result)
Next
' The example displays the following output:
' The Byte value 0 converts to 0.
' The Byte value 14 converts to 14.
' The Byte value 122 converts to 122.
' The Byte value 255 converts to 255.
適用対象
ToInt16(Boolean)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定したブール値を等価の 16 ビット符号付き整数に変換します。
public:
static short ToInt16(bool value);public static short ToInt16 (bool value);static member ToInt16 : bool -> int16Public Shared Function ToInt16 (value As Boolean) As Shortパラメーター
- value
- Boolean
変換するブール値。
戻り値
value が true の場合は数値の 1。それ以外の場合は 0。
例
次の例では、ブール値と false を 値trueにInt16変換します。
bool falseFlag = false;
bool trueFlag = true;
Console.WriteLine("{0} converts to {1}.", falseFlag,
Convert.ToInt16(falseFlag));
Console.WriteLine("{0} converts to {1}.", trueFlag,
Convert.ToInt16(trueFlag));
// The example displays the following output:
// False converts to 0.
// True converts to 1.
let falseFlag = false
let trueFlag = true
printfn $"{falseFlag} converts to {Convert.ToInt16 falseFlag}."
printfn $"{trueFlag} converts to {Convert.ToInt16 trueFlag}."
// The example displays the following output:
// False converts to 0.
// True converts to 1.
Dim falseFlag As Boolean = False
Dim trueFlag As Boolean = True
Console.WriteLine("{0} converts to {1}.", falseFlag, _
Convert.ToInt16(falseFlag))
Console.WriteLine("{0} converts to {1}.", trueFlag, _
Convert.ToInt16(trueFlag))
' The example displays the following output:
' False converts to 0.
' True converts to 1.
適用対象
ToInt16(Object)
- ソース:
- Convert.cs
- ソース:
- Convert.cs
- ソース:
- Convert.cs
指定したオブジェクトの値を 16 ビット符号付き整数に変換します。
public:
static short ToInt16(System::Object ^ value);public static short ToInt16 (object value);public static short ToInt16 (object? value);static member ToInt16 : obj -> int16Public Shared Function ToInt16 (value As Object) As Shortパラメーター
- value
- Object
IConvertible インターフェイスを実装するオブジェクトか、または null。
戻り値
value と等価の 16 ビット符号付き整数。value が null の場合は 0。
例外
value は Int16 型の適切な形式ではありません。
value は、 Int16.MinValue より小さいか、Int16.MaxValue より大きい数値 を表します。
例
次の例では、オブジェクト配列内の各要素を 16 ビット符号付き整数に変換しようとしています。
object[] values= { true, -12, 163, 935, 'x', new DateTime(2009, 5, 12),
"104", "103.0", "-1", "1.00e2", "One", 1.00e2};
short result;
foreach (object value in values)
{
try {
result = Convert.ToInt16(value);
Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
value.GetType().Name, value,
result.GetType().Name, result);
}
catch (OverflowException) {
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.",
value.GetType().Name, value);
}
catch (FormatException) {
Console.WriteLine("The {0} value {1} is not in a recognizable format.",
value.GetType().Name, value);
}
catch (InvalidCastException) {
Console.WriteLine("No conversion to an Int16 exists for the {0} value {1}.",
value.GetType().Name, value);
}
}
// The example displays the following output:
// Converted the Boolean value True to the Int16 value 1.
// Converted the Int32 value -12 to the Int16 value -12.
// Converted the Int32 value 163 to the Int16 value 163.
// Converted the Int32 value 935 to the Int16 value 935.
// Converted the Char value x to the Int16 value 120.
// No conversion to an Int16 exists for the DateTime value 5/12/2009 12:00:00 AM.
// Converted the String value 104 to the Int16 value 104.
// The String value 103.0 is not in a recognizable format.
// Converted the String value -1 to the Int16 value -1.
// The String value 1.00e2 is not in a recognizable format.
// The String value One is not in a recognizable format.
// Converted the Double value 100 to the Int16 value 100.
let values: obj[] =
[| true; -12; 163; 935; 'x'; DateTime(2009, 5, 12)
"104"; "103.0"; "-1"; "1.00e2"; "One"; 1.00e2 |]
for value in values do
try
let result = Convert.ToInt16 value
printfn $"Converted the {value.GetType().Name} value {value} to the {result.GetType().Name} value {result}."
with
| :? OverflowException ->
printfn $"The {value.GetType().Name} value {value} is outside the range of the Int16 type."
| :? FormatException ->
printfn $"The {value.GetType().Name} value {value} is not in a recognizable format."
| :? InvalidCastException ->
printfn $"No conversion to an Int16 exists for the {value.GetType().Name} value {value}."
// The example displays the following output:
// Converted the Boolean value True to the Int16 value 1.
// Converted the Int32 value -12 to the Int16 value -12.
// Converted the Int32 value 163 to the Int16 value 163.
// Converted the Int32 value 935 to the Int16 value 935.
// Converted the Char value x to the Int16 value 120.
// No conversion to an Int16 exists for the DateTime value 5/12/2009 12:00:00 AM.
// Converted the String value 104 to the Int16 value 104.
// The String value 103.0 is not in a recognizable format.
// Converted the String value -1 to the Int16 value -1.
// The String value 1.00e2 is not in a recognizable format.
// The String value One is not in a recognizable format.
// Converted the Double value 100 to the Int16 value 100.
Dim values() As Object = { True, -12, 163, 935, "x"c, #5/12/2009#, _
"104", "103.0", "-1", _
"1.00e2", "One", 1.00e2}
Dim result As Short
For Each value As Object In values
Try
result = Convert.ToInt16(value)
Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
value.GetType().Name, value, _
result.GetType().Name, result)
Catch e As OverflowException
Console.WriteLine("The {0} value {1} is outside the range of the Int16 type.", _
value.GetType().Name, value)
Catch e As FormatException
Console.WriteLine("The {0} value {1} is not in a recognizable format.", _
value.GetType().Name, value)
Catch e As InvalidCastException
Console.WriteLine("No conversion to an Int16 exists for the {0} value {1}.", _
value.GetType().Name, value)
End Try
Next
' The example displays the following output:
' Converted the Boolean value True to the Int16 value 1.
' Converted the Int32 value -12 to the Int16 value -12.
' Converted the Int32 value 163 to the Int16 value 163.
' Converted the Int32 value 935 to the Int16 value 935.
' Converted the Char value x to the Int16 value 120.
' No conversion to an Int16 exists for the DateTime value 5/12/2009 12:00:00 AM.
' Converted the String value 104 to the Int16 value 104.
' The String value 103.0 is not in a recognizable format.
' Converted the String value -1 to the Int16 value -1.
' The String value 1.00e2 is not in a recognizable format.
' The String value One is not in a recognizable format.
' Converted the Double value 100 to the Int16 value 100.
注釈
が でないnull場合value、このメソッドは、 の基になる型valueの実装のIConvertible.ToInt16呼び出しをラップします。
適用対象
GitHub で Microsoft と共同作業する
このコンテンツのソースは GitHub にあります。そこで、issue や pull request を作成および確認することもできます。 詳細については、共同作成者ガイドを参照してください。
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