Encoding.Unicode Propriété
Définition
Important
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Obtient un encodage pour le format UTF-16 avec primauté des octets de poids faible (little-endian).
public:
static property System::Text::Encoding ^ Unicode { System::Text::Encoding ^ get(); };public static System.Text.Encoding Unicode { get; }member this.Unicode : System.Text.EncodingPublic Shared ReadOnly Property Unicode As EncodingValeur de propriété
Encodage pour le format UTF-16 en utilisant l'ordre d'octet avec primauté des octets de poids faible (Little Endian).
Exemples
L’exemple suivant détermine le nombre d’octets requis pour encoder un tableau de caractères, encode les caractères et affiche les octets obtenus.
using namespace System;
using namespace System::Text;
void PrintCountsAndBytes( array<Char>^chars, Encoding^ enc );
void PrintHexBytes( array<Byte>^bytes );
int main()
{
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
array<Char>^myChars = gcnew array<Char>{
L'z','a',L'\u0306',L'\u01FD',L'\u03B2',L'\xD8FF',L'\xDCFF'
};
// Get different encodings.
Encoding^ u7 = Encoding::UTF7;
Encoding^ u8 = Encoding::UTF8;
Encoding^ u16LE = Encoding::Unicode;
Encoding^ u16BE = Encoding::BigEndianUnicode;
Encoding^ u32 = Encoding::UTF32;
// Encode the entire array, and print out the counts and the resulting bytes.
PrintCountsAndBytes( myChars, u7 );
PrintCountsAndBytes( myChars, u8 );
PrintCountsAndBytes( myChars, u16LE );
PrintCountsAndBytes( myChars, u16BE );
PrintCountsAndBytes( myChars, u32 );
}
void PrintCountsAndBytes( array<Char>^chars, Encoding^ enc )
{
// Display the name of the encoding used.
Console::Write( "{0,-30} :", enc );
// Display the exact byte count.
int iBC = enc->GetByteCount( chars );
Console::Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc->GetMaxByteCount( chars->Length );
Console::Write( " {0,-3} :", iMBC );
// Encode the array of chars.
array<Byte>^bytes = enc->GetBytes( chars );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
void PrintHexBytes( array<Byte>^bytes )
{
if ( (bytes == nullptr) || (bytes->Length == 0) )
Console::WriteLine( "<none>" );
else
{
for ( int i = 0; i < bytes->Length; i++ )
Console::Write( "{0:X2} ", bytes[ i ] );
Console::WriteLine();
}
}
/*
This code produces the following output.
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
*/
using System;
using System.Text;
public class SamplesEncoding {
public static void Main() {
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
char[] myChars = new char[] { 'z', 'a', '\u0306', '\u01FD', '\u03B2', '\uD8FF', '\uDCFF' };
// Get different encodings.
Encoding u7 = Encoding.UTF7;
Encoding u8 = Encoding.UTF8;
Encoding u16LE = Encoding.Unicode;
Encoding u16BE = Encoding.BigEndianUnicode;
Encoding u32 = Encoding.UTF32;
// Encode the entire array, and print out the counts and the resulting bytes.
PrintCountsAndBytes( myChars, u7 );
PrintCountsAndBytes( myChars, u8 );
PrintCountsAndBytes( myChars, u16LE );
PrintCountsAndBytes( myChars, u16BE );
PrintCountsAndBytes( myChars, u32 );
}
public static void PrintCountsAndBytes( char[] chars, Encoding enc ) {
// Display the name of the encoding used.
Console.Write( "{0,-30} :", enc.ToString() );
// Display the exact byte count.
int iBC = enc.GetByteCount( chars );
Console.Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount( chars.Length );
Console.Write( " {0,-3} :", iMBC );
// Encode the array of chars.
byte[] bytes = enc.GetBytes( chars );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
public static void PrintHexBytes( byte[] bytes ) {
if (( bytes == null ) || ( bytes.Length == 0 ))
{
Console.WriteLine( "<none>" );
}
else {
for ( int i = 0; i < bytes.Length; i++ )
Console.Write( "{0:X2} ", bytes[i] );
Console.WriteLine();
}
}
}
/*
This code produces the following output.
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
*/
Imports System.Text
Public Class SamplesEncoding
Public Shared Sub Main()
' The characters to encode:
' Latin Small Letter Z (U+007A)
' Latin Small Letter A (U+0061)
' Combining Breve (U+0306)
' Latin Small Letter AE With Acute (U+01FD)
' Greek Small Letter Beta (U+03B2)
' a high-surrogate value (U+D8FF)
' a low-surrogate value (U+DCFF)
Dim myChars() As Char = {"z"c, "a"c, ChrW(&H0306), ChrW(&H01FD), ChrW(&H03B2), ChrW(&HD8FF), ChrW(&HDCFF)}
' Get different encodings.
Dim u7 As Encoding = Encoding.UTF7
Dim u8 As Encoding = Encoding.UTF8
Dim u16LE As Encoding = Encoding.Unicode
Dim u16BE As Encoding = Encoding.BigEndianUnicode
Dim u32 As Encoding = Encoding.UTF32
' Encode the entire array, and print out the counts and the resulting bytes.
PrintCountsAndBytes(myChars, u7)
PrintCountsAndBytes(myChars, u8)
PrintCountsAndBytes(myChars, u16LE)
PrintCountsAndBytes(myChars, u16BE)
PrintCountsAndBytes(myChars, u32)
End Sub
Public Shared Sub PrintCountsAndBytes(chars() As Char, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(chars)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(chars.Length)
Console.Write(" {0,-3} :", iMBC)
' Encode the array of chars.
Dim bytes As Byte() = enc.GetBytes(chars)
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Public Shared Sub PrintHexBytes(bytes() As Byte)
If bytes Is Nothing OrElse bytes.Length = 0 Then
Console.WriteLine("<none>")
Else
Dim i As Integer
For i = 0 To bytes.Length - 1
Console.Write("{0:X2} ", bytes(i))
Next i
Console.WriteLine()
End If
End Sub
End Class
'This code produces the following output.
'
'System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
'System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
'System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
'System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
'System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
Remarques
Pour plus d’informations sur les encodages pris en charge par .NET et sur l’encodage Unicode à utiliser, consultez encodage de caractères dans .net.
L' UnicodeEncoding objet retourné par cette propriété n’a peut-être pas le comportement approprié pour votre application. Elle utilise l’option de secours de remplacement pour remplacer chaque chaîne qu’elle ne peut pas encoder et chaque octet qu’elle ne peut pas décoder par un point d’interrogation (« ? »). Au lieu de cela, vous pouvez appeler le UnicodeEncoding.UnicodeEncoding(Boolean, Boolean, Boolean) constructeur pour instancier un objet Little endian UnicodeEncoding dont EncoderFallbackException la valeur de secours est ou DecoderFallbackException , comme l’illustre l’exemple suivant.
using System;
using System.Text;
public class Example
{
public static void Main()
{
byte[] bytes = { 0x20, 0x00, 0x01, 0xD8, 0x68, 0x00, 0xA7, 0x00 };
Encoding enc = new UnicodeEncoding(false, true, true);
try {
string value = enc.GetString(bytes);
Console.WriteLine();
Console.WriteLine("'{0}'", value);
}
catch (DecoderFallbackException e) {
Console.WriteLine("Unable to decode {0} at index {1}",
ShowBytes(e.BytesUnknown), e.Index);
}
}
private static string ShowBytes(byte[] bytes)
{
string returnString = null;
foreach (var byteValue in bytes)
returnString += String.Format("0x{0:X2} ", byteValue);
return returnString.Trim();
}
}
// The example displays the following output:
// Unable to decode 0x01 0xD8 at index 4
Imports System.Text
Module Example
Public Sub Main()
Dim bytes() As Byte = { &h20, &h00, &h01, &hD8, &h68, &h00, &hA7, &h00}
Dim enc As Encoding = New UnicodeEncoding(False, True, True)
Try
Dim value As String = enc.GetString(bytes)
Console.WriteLine()
Console.WriteLine("'{0}'", value)
Catch e As DecoderFallbackException
Console.WriteLine("Unable to decode {0} at index {1}",
ShowBytes(e.BytesUnknown), e.Index)
End Try
End Sub
Private Function ShowBytes(bytes As Byte()) As String
Dim returnString As String = Nothing
For Each byteValue In bytes
returnString += String.Format("0x{0:X2} ", byteValue)
Next
Return returnString.Trim()
End Function
End Module
' The example displays the following output:
' Unable to decode 0x01 0xD8 at index 4