CustomAttributeData.GetCustomAttributes メソッド
定義
重要
一部の情報は、リリース前に大きく変更される可能性があるプレリリースされた製品に関するものです。 Microsoft は、ここに記載されている情報について、明示または黙示を問わず、一切保証しません。
対象に適用されている属性に関するデータを表す CustomAttributeData オブジェクトのリストを返します。
オーバーロード
GetCustomAttributes(Assembly) |
ターゲット アセンブリに適用されている属性に関するデータを表す CustomAttributeData オブジェクトのリストを返します。 |
GetCustomAttributes(MemberInfo) |
ターゲット メンバーに適用されている属性に関するデータを表す CustomAttributeData オブジェクトのリストを返します。 |
GetCustomAttributes(Module) |
ターゲット モジュールに適用されている属性に関するデータを表す CustomAttributeData オブジェクトのリストを戻します。 |
GetCustomAttributes(ParameterInfo) |
ターゲット パラメーターに適用されている属性に関するデータを表す CustomAttributeData オブジェクトのリストを戻します。 |
GetCustomAttributes(Assembly)
ターゲット アセンブリに適用されている属性に関するデータを表す CustomAttributeData オブジェクトのリストを返します。
public:
static System::Collections::Generic::IList<System::Reflection::CustomAttributeData ^> ^ GetCustomAttributes(System::Reflection::Assembly ^ target);
public static System.Collections.Generic.IList<System.Reflection.CustomAttributeData> GetCustomAttributes (System.Reflection.Assembly target);
static member GetCustomAttributes : System.Reflection.Assembly -> System.Collections.Generic.IList<System.Reflection.CustomAttributeData>
Public Shared Function GetCustomAttributes (target As Assembly) As IList(Of CustomAttributeData)
パラメーター
- target
- Assembly
取得するカスタム属性データが含まれるアセンブリ。
戻り値
ターゲット アセンブリに適用されている属性に関するデータを表すオブジェクトのリスト。
例外
target
が null
です。
例
次の例では、4 つのコンストラクターと 4 つのプロパティを持つカスタム属性を定義します。 2 つのプロパティは読み取り専用であり、コンストラクターの位置パラメーターを使用して設定されます。 他の 2 つのプロパティは読み取り/書き込みであり、名前付き引数を使用してのみ設定できます。 1 つの位置指定プロパティは文字列の配列であり、1 つの名前付きプロパティは整数の配列です。
この属性は、アセンブリ、アセンブリで宣言された型、型のメソッド、メソッドのパラメーターに適用されます。 このような場合は、さまざまなコンストラクターが使用されます。 アセンブリを実行すると、それ自体がリフレクションのみのコンテキストに読み込まれて、カスタム属性が表示されます。
型に適用される 属性は、位置引数と名前付き引数の両方を持つ配列プロパティを示しています。
メソッドは GetCustomAttributes 、 で Main()
使用され、アセンブリに適用されるカスタム属性を取得します。 メソッドの戻り値が メソッドに ShowAttributeData
渡されます。
using namespace System;
using namespace System::Reflection;
using namespace System::Collections::Generic;
using namespace System::Collections::ObjectModel;
// An enumeration used by the ExampleAttribute class.
public enum class ExampleKind
{
FirstKind, SecondKind, ThirdKind, FourthKind
};
// An example attribute. The attribute can be applied to all
// targets, from assemblies to parameters.
//
[AttributeUsage(AttributeTargets::All)]
public ref class ExampleAttribute: public Attribute
{
private:
// Data for properties.
ExampleKind kindValue;
String^ noteValue;
array<String^>^ arrayStrings;
array<int>^ arrayNumbers;
// Constructors.
void ExampleAttributeInitialize( ExampleKind initKind, array<String^>^ initStrings )
{
kindValue = initKind;
arrayStrings = initStrings;
}
public:
ExampleAttribute()
{
ExampleAttributeInitialize( ExampleKind::FirstKind, nullptr );
}
ExampleAttribute( ExampleKind initKind )
{
ExampleAttributeInitialize( initKind, nullptr );
}
ExampleAttribute( ExampleKind initKind, array<String^>^ initStrings )
{
ExampleAttributeInitialize( initKind, initStrings );
}
// Properties. The Note and Numbers properties must be read/write, so they
// can be used as named parameters.
//
property ExampleKind Kind
{
ExampleKind get()
{
return kindValue;
}
}
property array<String^>^ Strings
{
array<String^>^ get()
{
return arrayStrings;
}
}
property String^ Note
{
String^ get()
{
return noteValue;
}
void set( String^ value )
{
noteValue = value;
}
}
property array<int>^ Numbers
{
array<int>^ get()
{
return arrayNumbers;
}
void set( array<int>^ value )
{
arrayNumbers = value;
}
}
};
// The example attribute is applied to the assembly.
[assembly:Example(ExampleKind::ThirdKind,Note="This is a note on the assembly.")];
// The example attribute is applied to the test class.
//
[Example(ExampleKind::SecondKind,
gcnew array<String^> { "String array argument, line 1",
"String array argument, line 2",
"String array argument, line 3" },
Note="This is a note on the class.",
Numbers = gcnew array<int> { 53, 57, 59 })]
public ref class Test
{
public:
// The example attribute is applied to a method, using the
// parameterless constructor and supplying a named argument.
// The attribute is also applied to the method parameter.
//
[Example(Note="This is a note on a method.")]
void TestMethod( [Example] Object^ arg ){}
// Main() gets objects representing the assembly, the test
// type, the test method, and the method parameter. Custom
// attribute data is displayed for each of these.
//
static void Main()
{
Assembly^ assembly = Assembly::ReflectionOnlyLoad( "Source" );
Type^ t = assembly->GetType( "Test" );
MethodInfo^ m = t->GetMethod( "TestMethod" );
array<ParameterInfo^>^p = m->GetParameters();
Console::WriteLine( "\r\nAttributes for assembly: '{0}'", assembly );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( assembly ) );
Console::WriteLine( "\r\nAttributes for type: '{0}'", t );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( t ) );
Console::WriteLine( "\r\nAttributes for member: '{0}'", m );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( m ) );
Console::WriteLine( "\r\nAttributes for parameter: '{0}'", p );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( p[ 0 ] ) );
}
private:
static void ShowValueOrArray(CustomAttributeTypedArgument^ cata)
{
if (cata->Value->GetType() == ReadOnlyCollection<CustomAttributeTypedArgument>::typeid)
{
Console::WriteLine(" Array of '{0}':", cata->ArgumentType);
for each (CustomAttributeTypedArgument^ cataElement in
(ReadOnlyCollection<CustomAttributeTypedArgument>^) cata->Value)
{
Console::WriteLine(" Type: '{0}' Value: '{1}'",
cataElement->ArgumentType, cataElement->Value);
}
}
else
{
Console::WriteLine( " Type: '{0}' Value: '{1}'",
cata->ArgumentType, cata->Value );
}
}
static void ShowAttributeData( IList< CustomAttributeData^ >^ attributes )
{
for each ( CustomAttributeData^ cad in attributes )
{
Console::WriteLine( " {0}", cad );
Console::WriteLine( " Constructor: '{0}'", cad->Constructor );
Console::WriteLine( " Constructor arguments:" );
for each ( CustomAttributeTypedArgument^ cata in cad->ConstructorArguments )
{
ShowValueOrArray(cata);
}
Console::WriteLine( " Named arguments:" );
for each ( CustomAttributeNamedArgument cana in cad->NamedArguments )
{
Console::WriteLine( " MemberInfo: '{0}'", cana.MemberInfo );
ShowValueOrArray(cana.TypedValue);
}
}
}
};
int main()
{
Test::Main();
}
/* This code example produces output similar to the following:
Attributes for assembly: 'source, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'
[System.Runtime.CompilerServices.CompilationRelaxationsAttribute((Int32)8)]
Constructor: 'Void .ctor(Int32)'
Constructor arguments:
Type: 'System.Int32' Value: '8'
Named arguments:
[System.Runtime.CompilerServices.RuntimeCompatibilityAttribute(WrapNonExceptionThrows = True)]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'Boolean WrapNonExceptionThrows'
Type: 'System.Boolean' Value: 'True'
[ExampleAttribute((ExampleKind)2, Note = "This is a note on the assembly.")]
Constructor: 'Void .ctor(ExampleKind)'
Constructor arguments:
Type: 'ExampleKind' Value: '2'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the assembly.'
Attributes for type: 'Test'
[ExampleAttribute((ExampleKind)1, new String[3] { "String array argument, line 1", "String array argument, line 2", "String array argument, line 3" }, Note = "This is a note on the class.", Numbers = new Int32[3] { 53, 57, 59 })]
Constructor: 'Void .ctor(ExampleKind, System.String[])'
Constructor arguments:
Type: 'ExampleKind' Value: '1'
Array of 'System.String[]':
Type: 'System.String' Value: 'String array argument, line 1'
Type: 'System.String' Value: 'String array argument, line 2'
Type: 'System.String' Value: 'String array argument, line 3'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the class.'
MemberInfo: 'Int32[] Numbers'
Array of 'System.Int32[]':
Type: 'System.Int32' Value: '53'
Type: 'System.Int32' Value: '57'
Type: 'System.Int32' Value: '59'
Attributes for member: 'Void TestMethod(System.Object)'
[ExampleAttribute(Note = "This is a note on a method.")]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on a method.'
Attributes for parameter: 'System.Object arg'
[ExampleAttribute()]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
*/
using System;
using System.Reflection;
using System.Collections.Generic;
using System.Collections.ObjectModel;
// The example attribute is applied to the assembly.
[assembly:Example(ExampleKind.ThirdKind, Note="This is a note on the assembly.")]
// An enumeration used by the ExampleAttribute class.
public enum ExampleKind
{
FirstKind,
SecondKind,
ThirdKind,
FourthKind
};
// An example attribute. The attribute can be applied to all
// targets, from assemblies to parameters.
//
[AttributeUsage(AttributeTargets.All)]
public class ExampleAttribute : Attribute
{
// Data for properties.
private ExampleKind kindValue;
private string noteValue;
private string[] arrayStrings;
private int[] arrayNumbers;
// Constructors. The parameterless constructor (.ctor) calls
// the constructor that specifies ExampleKind and an array of
// strings, and supplies the default values.
//
public ExampleAttribute(ExampleKind initKind, string[] initStrings)
{
kindValue = initKind;
arrayStrings = initStrings;
}
public ExampleAttribute(ExampleKind initKind) : this(initKind, null) {}
public ExampleAttribute() : this(ExampleKind.FirstKind, null) {}
// Properties. The Note and Numbers properties must be read/write, so they
// can be used as named parameters.
//
public ExampleKind Kind { get { return kindValue; }}
public string[] Strings { get { return arrayStrings; }}
public string Note
{
get { return noteValue; }
set { noteValue = value; }
}
public int[] Numbers
{
get { return arrayNumbers; }
set { arrayNumbers = value; }
}
}
// The example attribute is applied to the test class.
//
[Example(ExampleKind.SecondKind,
new string[] { "String array argument, line 1",
"String array argument, line 2",
"String array argument, line 3" },
Note="This is a note on the class.",
Numbers = new int[] { 53, 57, 59 })]
public class Test
{
// The example attribute is applied to a method, using the
// parameterless constructor and supplying a named argument.
// The attribute is also applied to the method parameter.
//
[Example(Note="This is a note on a method.")]
public void TestMethod([Example] object arg) { }
// Main() gets objects representing the assembly, the test
// type, the test method, and the method parameter. Custom
// attribute data is displayed for each of these.
//
public static void Main()
{
Assembly asm = Assembly.ReflectionOnlyLoad("Source");
Type t = asm.GetType("Test");
MethodInfo m = t.GetMethod("TestMethod");
ParameterInfo[] p = m.GetParameters();
Console.WriteLine("\r\nAttributes for assembly: '{0}'", asm);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(asm));
Console.WriteLine("\r\nAttributes for type: '{0}'", t);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(t));
Console.WriteLine("\r\nAttributes for member: '{0}'", m);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(m));
Console.WriteLine("\r\nAttributes for parameter: '{0}'", p);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(p[0]));
}
private static void ShowAttributeData(
IList<CustomAttributeData> attributes)
{
foreach( CustomAttributeData cad in attributes )
{
Console.WriteLine(" {0}", cad);
Console.WriteLine(" Constructor: '{0}'", cad.Constructor);
Console.WriteLine(" Constructor arguments:");
foreach( CustomAttributeTypedArgument cata
in cad.ConstructorArguments )
{
ShowValueOrArray(cata);
}
Console.WriteLine(" Named arguments:");
foreach( CustomAttributeNamedArgument cana
in cad.NamedArguments )
{
Console.WriteLine(" MemberInfo: '{0}'",
cana.MemberInfo);
ShowValueOrArray(cana.TypedValue);
}
}
}
private static void ShowValueOrArray(CustomAttributeTypedArgument cata)
{
if (cata.Value.GetType() == typeof(ReadOnlyCollection<CustomAttributeTypedArgument>))
{
Console.WriteLine(" Array of '{0}':", cata.ArgumentType);
foreach (CustomAttributeTypedArgument cataElement in
(ReadOnlyCollection<CustomAttributeTypedArgument>) cata.Value)
{
Console.WriteLine(" Type: '{0}' Value: '{1}'",
cataElement.ArgumentType, cataElement.Value);
}
}
else
{
Console.WriteLine(" Type: '{0}' Value: '{1}'",
cata.ArgumentType, cata.Value);
}
}
}
/* This code example produces output similar to the following:
Attributes for assembly: 'source, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'
[System.Runtime.CompilerServices.CompilationRelaxationsAttribute((Int32)8)]
Constructor: 'Void .ctor(Int32)'
Constructor arguments:
Type: 'System.Int32' Value: '8'
Named arguments:
[System.Runtime.CompilerServices.RuntimeCompatibilityAttribute(WrapNonExceptionThrows = True)]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'Boolean WrapNonExceptionThrows'
Type: 'System.Boolean' Value: 'True'
[ExampleAttribute((ExampleKind)2, Note = "This is a note on the assembly.")]
Constructor: 'Void .ctor(ExampleKind)'
Constructor arguments:
Type: 'ExampleKind' Value: '2'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the assembly.'
Attributes for type: 'Test'
[ExampleAttribute((ExampleKind)1, new String[3] { "String array argument, line 1", "String array argument, line 2", "String array argument, line 3" }, Note = "This is a note on the class.", Numbers = new Int32[3] { 53, 57, 59 })]
Constructor: 'Void .ctor(ExampleKind, System.String[])'
Constructor arguments:
Type: 'ExampleKind' Value: '1'
Array of 'System.String[]':
Type: 'System.String' Value: 'String array argument, line 1'
Type: 'System.String' Value: 'String array argument, line 2'
Type: 'System.String' Value: 'String array argument, line 3'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the class.'
MemberInfo: 'Int32[] Numbers'
Array of 'System.Int32[]':
Type: 'System.Int32' Value: '53'
Type: 'System.Int32' Value: '57'
Type: 'System.Int32' Value: '59'
Attributes for member: 'Void TestMethod(System.Object)'
[ExampleAttribute(Note = "This is a note on a method.")]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on a method.'
Attributes for parameter: 'System.Object arg'
[ExampleAttribute()]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
*/
Imports System.Reflection
Imports System.Collections.Generic
Imports System.Collections.ObjectModel
' The example attribute is applied to the assembly.
<Assembly:Example(ExampleKind.ThirdKind, Note:="This is a note on the assembly.")>
' An enumeration used by the ExampleAttribute class.
Public Enum ExampleKind
FirstKind
SecondKind
ThirdKind
FourthKind
End Enum
' An example attribute. The attribute can be applied to all
' targets, from assemblies to parameters.
'
<AttributeUsage(AttributeTargets.All)> _
Public Class ExampleAttribute
Inherits Attribute
' Data for properties.
Private kindValue As ExampleKind
Private noteValue As String
Private arrayStrings() As String
Private arrayNumbers() As Integer
' Constructors. The parameterless constructor (.ctor) calls
' the constructor that specifies ExampleKind and an array of
' strings, and supplies the default values.
'
Public Sub New(ByVal initKind As ExampleKind, ByVal initStrings() As String)
kindValue = initKind
arrayStrings = initStrings
End Sub
Public Sub New(ByVal initKind As ExampleKind)
Me.New(initKind, Nothing)
End Sub
Public Sub New()
Me.New(ExampleKind.FirstKind, Nothing)
End Sub
' Properties. The Note and Numbers properties must be read/write, so they
' can be used as named parameters.
'
Public ReadOnly Property Kind As ExampleKind
Get
Return kindValue
End Get
End Property
Public ReadOnly Property Strings As String()
Get
Return arrayStrings
End Get
End Property
Public Property Note As String
Get
Return noteValue
End Get
Set
noteValue = value
End Set
End Property
Public Property Numbers As Integer()
Get
Return arrayNumbers
End Get
Set
arrayNumbers = value
End Set
End Property
End Class
' The example attribute is applied to the test class.
'
<Example(ExampleKind.SecondKind, _
New String() { "String array argument, line 1", _
"String array argument, line 2", _
"String array argument, line 3" }, _
Note := "This is a note on the class.", _
Numbers := New Integer() { 53, 57, 59 })> _
Public Class Test
' The example attribute is applied to a method, using the
' parameterless constructor and supplying a named argument.
' The attribute is also applied to the method parameter.
'
<Example(Note:="This is a note on a method.")> _
Public Sub TestMethod(<Example()> ByVal arg As Object)
End Sub
' Sub Main gets objects representing the assembly, the test
' type, the test method, and the method parameter. Custom
' attribute data is displayed for each of these.
'
Public Shared Sub Main()
Dim asm As [Assembly] = Assembly.ReflectionOnlyLoad("source")
Dim t As Type = asm.GetType("Test")
Dim m As MethodInfo = t.GetMethod("TestMethod")
Dim p() As ParameterInfo = m.GetParameters()
Console.WriteLine(vbCrLf & "Attributes for assembly: '{0}'", asm)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(asm))
Console.WriteLine(vbCrLf & "Attributes for type: '{0}'", t)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(t))
Console.WriteLine(vbCrLf & "Attributes for member: '{0}'", m)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(m))
Console.WriteLine(vbCrLf & "Attributes for parameter: '{0}'", p)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(p(0)))
End Sub
Private Shared Sub ShowAttributeData( _
ByVal attributes As IList(Of CustomAttributeData))
For Each cad As CustomAttributeData _
In CType(attributes, IEnumerable(Of CustomAttributeData))
Console.WriteLine(" {0}", cad)
Console.WriteLine(" Constructor: '{0}'", cad.Constructor)
Console.WriteLine(" Constructor arguments:")
For Each cata As CustomAttributeTypedArgument _
In CType(cad.ConstructorArguments, IEnumerable(Of CustomAttributeTypedArgument))
ShowValueOrArray(cata)
Next
Console.WriteLine(" Named arguments:")
For Each cana As CustomAttributeNamedArgument _
In CType(cad.NamedArguments, IEnumerable(Of CustomAttributeNamedArgument))
Console.WriteLine(" MemberInfo: '{0}'", _
cana.MemberInfo)
ShowValueOrArray(cana.TypedValue)
Next
Next
End Sub
Private Shared Sub ShowValueOrArray(ByVal cata As CustomAttributeTypedArgument)
If cata.Value.GetType() Is GetType(ReadOnlyCollection(Of CustomAttributeTypedArgument)) Then
Console.WriteLine(" Array of '{0}':", cata.ArgumentType)
For Each cataElement As CustomAttributeTypedArgument In cata.Value
Console.WriteLine(" Type: '{0}' Value: '{1}'", _
cataElement.ArgumentType, cataElement.Value)
Next
Else
Console.WriteLine(" Type: '{0}' Value: '{1}'", _
cata.ArgumentType, cata.Value)
End If
End Sub
End Class
' This code example produces output similar to the following:
'
'Attributes for assembly: 'source, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'
' [System.Runtime.CompilerServices.CompilationRelaxationsAttribute((Int32)8)]
' Constructor: 'Void .ctor(Int32)'
' Constructor arguments:
' Type: 'System.Int32' Value: '8'
' Named arguments:
' [System.Runtime.CompilerServices.RuntimeCompatibilityAttribute(WrapNonExceptionThrows = True)]
' Constructor: 'Void .ctor()'
' Constructor arguments:
' Named arguments:
' MemberInfo: 'Boolean WrapNonExceptionThrows'
' Type: 'System.Boolean' Value: 'True'
' [ExampleAttribute((ExampleKind)2, Note = "This is a note on the assembly.")]
' Constructor: 'Void .ctor(ExampleKind)'
' Constructor arguments:
' Type: 'ExampleKind' Value: '2'
' Named arguments:
' MemberInfo: 'System.String Note'
' Type: 'System.String' Value: 'This is a note on the assembly.'
'
'Attributes for type: 'Test'
' [ExampleAttribute((ExampleKind)1, new String[3] { "String array argument, line 1", "String array argument, line 2", "String array argument, line 3" }, Note = "This is a note on the class.", Numbers = new Int32[3] { 53, 57, 59 })]
' Constructor: 'Void .ctor(ExampleKind, System.String[])'
' Constructor arguments:
' Type: 'ExampleKind' Value: '1'
' Array of 'System.String[]':
' Type: 'System.String' Value: 'String array argument, line 1'
' Type: 'System.String' Value: 'String array argument, line 2'
' Type: 'System.String' Value: 'String array argument, line 3'
' Named arguments:
' MemberInfo: 'System.String Note'
' Type: 'System.String' Value: 'This is a note on the class.'
' MemberInfo: 'Int32[] Numbers'
' Array of 'System.Int32[]':
' Type: 'System.Int32' Value: '53'
' Type: 'System.Int32' Value: '57'
' Type: 'System.Int32' Value: '59'
'
'Attributes for member: 'Void TestMethod(System.Object)'
' [ExampleAttribute(Note = "This is a note on a method.")]
' Constructor: 'Void .ctor()'
' Constructor arguments:
' Named arguments:
' MemberInfo: 'System.String Note'
' Type: 'System.String' Value: 'This is a note on a method.'
'
'Attributes for parameter: 'System.Object arg'
' [ExampleAttribute()]
' Constructor: 'Void .ctor()'
' Constructor arguments:
' Named arguments:
注釈
このメソッドは、リフレクションのみのコンテキストで常に使用できる メソッドに代わる方法 GetCustomAttributes を提供します。
こちらもご覧ください
適用対象
GetCustomAttributes(MemberInfo)
ターゲット メンバーに適用されている属性に関するデータを表す CustomAttributeData オブジェクトのリストを返します。
public:
static System::Collections::Generic::IList<System::Reflection::CustomAttributeData ^> ^ GetCustomAttributes(System::Reflection::MemberInfo ^ target);
public static System.Collections.Generic.IList<System.Reflection.CustomAttributeData> GetCustomAttributes (System.Reflection.MemberInfo target);
static member GetCustomAttributes : System.Reflection.MemberInfo -> System.Collections.Generic.IList<System.Reflection.CustomAttributeData>
Public Shared Function GetCustomAttributes (target As MemberInfo) As IList(Of CustomAttributeData)
パラメーター
- target
- MemberInfo
取得する属性データが含まれるメンバー。
戻り値
ターゲット メンバーに適用されている属性に関するデータを表すオブジェクトのリスト。
例外
target
が null
です。
例
次の例では、4 つのコンストラクターと 4 つのプロパティを持つカスタム属性を定義します。 2 つのプロパティは読み取り専用であり、コンストラクターの位置パラメーターを使用して設定されます。 他の 2 つのプロパティは読み取り/書き込みであり、名前付き引数を使用してのみ設定できます。 1 つの位置指定プロパティは文字列の配列であり、1 つの名前付きプロパティは整数の配列です。
この属性は、アセンブリ、アセンブリで宣言された型、型のメソッド、メソッドのパラメーターに適用されます。 このような場合は、さまざまなコンストラクターが使用されます。 アセンブリを実行すると、それ自体がリフレクションのみのコンテキストに読み込まれて、カスタム属性が表示されます。
型に適用される 属性は、位置引数と名前付き引数の両方を持つ配列プロパティを示しています。
メソッドは GetCustomAttributes 、 で Main()
、型とテスト メソッドに適用されたカスタム属性を取得するために使用されます (Type から MemberInfo派生します)。 の GetCustomAttributes 戻り値が メソッドに ShowAttributeData
渡されます。
using namespace System;
using namespace System::Reflection;
using namespace System::Collections::Generic;
using namespace System::Collections::ObjectModel;
// An enumeration used by the ExampleAttribute class.
public enum class ExampleKind
{
FirstKind, SecondKind, ThirdKind, FourthKind
};
// An example attribute. The attribute can be applied to all
// targets, from assemblies to parameters.
//
[AttributeUsage(AttributeTargets::All)]
public ref class ExampleAttribute: public Attribute
{
private:
// Data for properties.
ExampleKind kindValue;
String^ noteValue;
array<String^>^ arrayStrings;
array<int>^ arrayNumbers;
// Constructors.
void ExampleAttributeInitialize( ExampleKind initKind, array<String^>^ initStrings )
{
kindValue = initKind;
arrayStrings = initStrings;
}
public:
ExampleAttribute()
{
ExampleAttributeInitialize( ExampleKind::FirstKind, nullptr );
}
ExampleAttribute( ExampleKind initKind )
{
ExampleAttributeInitialize( initKind, nullptr );
}
ExampleAttribute( ExampleKind initKind, array<String^>^ initStrings )
{
ExampleAttributeInitialize( initKind, initStrings );
}
// Properties. The Note and Numbers properties must be read/write, so they
// can be used as named parameters.
//
property ExampleKind Kind
{
ExampleKind get()
{
return kindValue;
}
}
property array<String^>^ Strings
{
array<String^>^ get()
{
return arrayStrings;
}
}
property String^ Note
{
String^ get()
{
return noteValue;
}
void set( String^ value )
{
noteValue = value;
}
}
property array<int>^ Numbers
{
array<int>^ get()
{
return arrayNumbers;
}
void set( array<int>^ value )
{
arrayNumbers = value;
}
}
};
// The example attribute is applied to the assembly.
[assembly:Example(ExampleKind::ThirdKind,Note="This is a note on the assembly.")];
// The example attribute is applied to the test class.
//
[Example(ExampleKind::SecondKind,
gcnew array<String^> { "String array argument, line 1",
"String array argument, line 2",
"String array argument, line 3" },
Note="This is a note on the class.",
Numbers = gcnew array<int> { 53, 57, 59 })]
public ref class Test
{
public:
// The example attribute is applied to a method, using the
// parameterless constructor and supplying a named argument.
// The attribute is also applied to the method parameter.
//
[Example(Note="This is a note on a method.")]
void TestMethod( [Example] Object^ arg ){}
// Main() gets objects representing the assembly, the test
// type, the test method, and the method parameter. Custom
// attribute data is displayed for each of these.
//
static void Main()
{
Assembly^ assembly = Assembly::ReflectionOnlyLoad( "Source" );
Type^ t = assembly->GetType( "Test" );
MethodInfo^ m = t->GetMethod( "TestMethod" );
array<ParameterInfo^>^p = m->GetParameters();
Console::WriteLine( "\r\nAttributes for assembly: '{0}'", assembly );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( assembly ) );
Console::WriteLine( "\r\nAttributes for type: '{0}'", t );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( t ) );
Console::WriteLine( "\r\nAttributes for member: '{0}'", m );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( m ) );
Console::WriteLine( "\r\nAttributes for parameter: '{0}'", p );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( p[ 0 ] ) );
}
private:
static void ShowValueOrArray(CustomAttributeTypedArgument^ cata)
{
if (cata->Value->GetType() == ReadOnlyCollection<CustomAttributeTypedArgument>::typeid)
{
Console::WriteLine(" Array of '{0}':", cata->ArgumentType);
for each (CustomAttributeTypedArgument^ cataElement in
(ReadOnlyCollection<CustomAttributeTypedArgument>^) cata->Value)
{
Console::WriteLine(" Type: '{0}' Value: '{1}'",
cataElement->ArgumentType, cataElement->Value);
}
}
else
{
Console::WriteLine( " Type: '{0}' Value: '{1}'",
cata->ArgumentType, cata->Value );
}
}
static void ShowAttributeData( IList< CustomAttributeData^ >^ attributes )
{
for each ( CustomAttributeData^ cad in attributes )
{
Console::WriteLine( " {0}", cad );
Console::WriteLine( " Constructor: '{0}'", cad->Constructor );
Console::WriteLine( " Constructor arguments:" );
for each ( CustomAttributeTypedArgument^ cata in cad->ConstructorArguments )
{
ShowValueOrArray(cata);
}
Console::WriteLine( " Named arguments:" );
for each ( CustomAttributeNamedArgument cana in cad->NamedArguments )
{
Console::WriteLine( " MemberInfo: '{0}'", cana.MemberInfo );
ShowValueOrArray(cana.TypedValue);
}
}
}
};
int main()
{
Test::Main();
}
/* This code example produces output similar to the following:
Attributes for assembly: 'source, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'
[System.Runtime.CompilerServices.CompilationRelaxationsAttribute((Int32)8)]
Constructor: 'Void .ctor(Int32)'
Constructor arguments:
Type: 'System.Int32' Value: '8'
Named arguments:
[System.Runtime.CompilerServices.RuntimeCompatibilityAttribute(WrapNonExceptionThrows = True)]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'Boolean WrapNonExceptionThrows'
Type: 'System.Boolean' Value: 'True'
[ExampleAttribute((ExampleKind)2, Note = "This is a note on the assembly.")]
Constructor: 'Void .ctor(ExampleKind)'
Constructor arguments:
Type: 'ExampleKind' Value: '2'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the assembly.'
Attributes for type: 'Test'
[ExampleAttribute((ExampleKind)1, new String[3] { "String array argument, line 1", "String array argument, line 2", "String array argument, line 3" }, Note = "This is a note on the class.", Numbers = new Int32[3] { 53, 57, 59 })]
Constructor: 'Void .ctor(ExampleKind, System.String[])'
Constructor arguments:
Type: 'ExampleKind' Value: '1'
Array of 'System.String[]':
Type: 'System.String' Value: 'String array argument, line 1'
Type: 'System.String' Value: 'String array argument, line 2'
Type: 'System.String' Value: 'String array argument, line 3'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the class.'
MemberInfo: 'Int32[] Numbers'
Array of 'System.Int32[]':
Type: 'System.Int32' Value: '53'
Type: 'System.Int32' Value: '57'
Type: 'System.Int32' Value: '59'
Attributes for member: 'Void TestMethod(System.Object)'
[ExampleAttribute(Note = "This is a note on a method.")]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on a method.'
Attributes for parameter: 'System.Object arg'
[ExampleAttribute()]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
*/
using System;
using System.Reflection;
using System.Collections.Generic;
using System.Collections.ObjectModel;
// The example attribute is applied to the assembly.
[assembly:Example(ExampleKind.ThirdKind, Note="This is a note on the assembly.")]
// An enumeration used by the ExampleAttribute class.
public enum ExampleKind
{
FirstKind,
SecondKind,
ThirdKind,
FourthKind
};
// An example attribute. The attribute can be applied to all
// targets, from assemblies to parameters.
//
[AttributeUsage(AttributeTargets.All)]
public class ExampleAttribute : Attribute
{
// Data for properties.
private ExampleKind kindValue;
private string noteValue;
private string[] arrayStrings;
private int[] arrayNumbers;
// Constructors. The parameterless constructor (.ctor) calls
// the constructor that specifies ExampleKind and an array of
// strings, and supplies the default values.
//
public ExampleAttribute(ExampleKind initKind, string[] initStrings)
{
kindValue = initKind;
arrayStrings = initStrings;
}
public ExampleAttribute(ExampleKind initKind) : this(initKind, null) {}
public ExampleAttribute() : this(ExampleKind.FirstKind, null) {}
// Properties. The Note and Numbers properties must be read/write, so they
// can be used as named parameters.
//
public ExampleKind Kind { get { return kindValue; }}
public string[] Strings { get { return arrayStrings; }}
public string Note
{
get { return noteValue; }
set { noteValue = value; }
}
public int[] Numbers
{
get { return arrayNumbers; }
set { arrayNumbers = value; }
}
}
// The example attribute is applied to the test class.
//
[Example(ExampleKind.SecondKind,
new string[] { "String array argument, line 1",
"String array argument, line 2",
"String array argument, line 3" },
Note="This is a note on the class.",
Numbers = new int[] { 53, 57, 59 })]
public class Test
{
// The example attribute is applied to a method, using the
// parameterless constructor and supplying a named argument.
// The attribute is also applied to the method parameter.
//
[Example(Note="This is a note on a method.")]
public void TestMethod([Example] object arg) { }
// Main() gets objects representing the assembly, the test
// type, the test method, and the method parameter. Custom
// attribute data is displayed for each of these.
//
public static void Main()
{
Assembly asm = Assembly.ReflectionOnlyLoad("Source");
Type t = asm.GetType("Test");
MethodInfo m = t.GetMethod("TestMethod");
ParameterInfo[] p = m.GetParameters();
Console.WriteLine("\r\nAttributes for assembly: '{0}'", asm);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(asm));
Console.WriteLine("\r\nAttributes for type: '{0}'", t);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(t));
Console.WriteLine("\r\nAttributes for member: '{0}'", m);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(m));
Console.WriteLine("\r\nAttributes for parameter: '{0}'", p);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(p[0]));
}
private static void ShowAttributeData(
IList<CustomAttributeData> attributes)
{
foreach( CustomAttributeData cad in attributes )
{
Console.WriteLine(" {0}", cad);
Console.WriteLine(" Constructor: '{0}'", cad.Constructor);
Console.WriteLine(" Constructor arguments:");
foreach( CustomAttributeTypedArgument cata
in cad.ConstructorArguments )
{
ShowValueOrArray(cata);
}
Console.WriteLine(" Named arguments:");
foreach( CustomAttributeNamedArgument cana
in cad.NamedArguments )
{
Console.WriteLine(" MemberInfo: '{0}'",
cana.MemberInfo);
ShowValueOrArray(cana.TypedValue);
}
}
}
private static void ShowValueOrArray(CustomAttributeTypedArgument cata)
{
if (cata.Value.GetType() == typeof(ReadOnlyCollection<CustomAttributeTypedArgument>))
{
Console.WriteLine(" Array of '{0}':", cata.ArgumentType);
foreach (CustomAttributeTypedArgument cataElement in
(ReadOnlyCollection<CustomAttributeTypedArgument>) cata.Value)
{
Console.WriteLine(" Type: '{0}' Value: '{1}'",
cataElement.ArgumentType, cataElement.Value);
}
}
else
{
Console.WriteLine(" Type: '{0}' Value: '{1}'",
cata.ArgumentType, cata.Value);
}
}
}
/* This code example produces output similar to the following:
Attributes for assembly: 'source, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'
[System.Runtime.CompilerServices.CompilationRelaxationsAttribute((Int32)8)]
Constructor: 'Void .ctor(Int32)'
Constructor arguments:
Type: 'System.Int32' Value: '8'
Named arguments:
[System.Runtime.CompilerServices.RuntimeCompatibilityAttribute(WrapNonExceptionThrows = True)]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'Boolean WrapNonExceptionThrows'
Type: 'System.Boolean' Value: 'True'
[ExampleAttribute((ExampleKind)2, Note = "This is a note on the assembly.")]
Constructor: 'Void .ctor(ExampleKind)'
Constructor arguments:
Type: 'ExampleKind' Value: '2'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the assembly.'
Attributes for type: 'Test'
[ExampleAttribute((ExampleKind)1, new String[3] { "String array argument, line 1", "String array argument, line 2", "String array argument, line 3" }, Note = "This is a note on the class.", Numbers = new Int32[3] { 53, 57, 59 })]
Constructor: 'Void .ctor(ExampleKind, System.String[])'
Constructor arguments:
Type: 'ExampleKind' Value: '1'
Array of 'System.String[]':
Type: 'System.String' Value: 'String array argument, line 1'
Type: 'System.String' Value: 'String array argument, line 2'
Type: 'System.String' Value: 'String array argument, line 3'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the class.'
MemberInfo: 'Int32[] Numbers'
Array of 'System.Int32[]':
Type: 'System.Int32' Value: '53'
Type: 'System.Int32' Value: '57'
Type: 'System.Int32' Value: '59'
Attributes for member: 'Void TestMethod(System.Object)'
[ExampleAttribute(Note = "This is a note on a method.")]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on a method.'
Attributes for parameter: 'System.Object arg'
[ExampleAttribute()]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
*/
Imports System.Reflection
Imports System.Collections.Generic
Imports System.Collections.ObjectModel
' The example attribute is applied to the assembly.
<Assembly:Example(ExampleKind.ThirdKind, Note:="This is a note on the assembly.")>
' An enumeration used by the ExampleAttribute class.
Public Enum ExampleKind
FirstKind
SecondKind
ThirdKind
FourthKind
End Enum
' An example attribute. The attribute can be applied to all
' targets, from assemblies to parameters.
'
<AttributeUsage(AttributeTargets.All)> _
Public Class ExampleAttribute
Inherits Attribute
' Data for properties.
Private kindValue As ExampleKind
Private noteValue As String
Private arrayStrings() As String
Private arrayNumbers() As Integer
' Constructors. The parameterless constructor (.ctor) calls
' the constructor that specifies ExampleKind and an array of
' strings, and supplies the default values.
'
Public Sub New(ByVal initKind As ExampleKind, ByVal initStrings() As String)
kindValue = initKind
arrayStrings = initStrings
End Sub
Public Sub New(ByVal initKind As ExampleKind)
Me.New(initKind, Nothing)
End Sub
Public Sub New()
Me.New(ExampleKind.FirstKind, Nothing)
End Sub
' Properties. The Note and Numbers properties must be read/write, so they
' can be used as named parameters.
'
Public ReadOnly Property Kind As ExampleKind
Get
Return kindValue
End Get
End Property
Public ReadOnly Property Strings As String()
Get
Return arrayStrings
End Get
End Property
Public Property Note As String
Get
Return noteValue
End Get
Set
noteValue = value
End Set
End Property
Public Property Numbers As Integer()
Get
Return arrayNumbers
End Get
Set
arrayNumbers = value
End Set
End Property
End Class
' The example attribute is applied to the test class.
'
<Example(ExampleKind.SecondKind, _
New String() { "String array argument, line 1", _
"String array argument, line 2", _
"String array argument, line 3" }, _
Note := "This is a note on the class.", _
Numbers := New Integer() { 53, 57, 59 })> _
Public Class Test
' The example attribute is applied to a method, using the
' parameterless constructor and supplying a named argument.
' The attribute is also applied to the method parameter.
'
<Example(Note:="This is a note on a method.")> _
Public Sub TestMethod(<Example()> ByVal arg As Object)
End Sub
' Sub Main gets objects representing the assembly, the test
' type, the test method, and the method parameter. Custom
' attribute data is displayed for each of these.
'
Public Shared Sub Main()
Dim asm As [Assembly] = Assembly.ReflectionOnlyLoad("source")
Dim t As Type = asm.GetType("Test")
Dim m As MethodInfo = t.GetMethod("TestMethod")
Dim p() As ParameterInfo = m.GetParameters()
Console.WriteLine(vbCrLf & "Attributes for assembly: '{0}'", asm)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(asm))
Console.WriteLine(vbCrLf & "Attributes for type: '{0}'", t)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(t))
Console.WriteLine(vbCrLf & "Attributes for member: '{0}'", m)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(m))
Console.WriteLine(vbCrLf & "Attributes for parameter: '{0}'", p)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(p(0)))
End Sub
Private Shared Sub ShowAttributeData( _
ByVal attributes As IList(Of CustomAttributeData))
For Each cad As CustomAttributeData _
In CType(attributes, IEnumerable(Of CustomAttributeData))
Console.WriteLine(" {0}", cad)
Console.WriteLine(" Constructor: '{0}'", cad.Constructor)
Console.WriteLine(" Constructor arguments:")
For Each cata As CustomAttributeTypedArgument _
In CType(cad.ConstructorArguments, IEnumerable(Of CustomAttributeTypedArgument))
ShowValueOrArray(cata)
Next
Console.WriteLine(" Named arguments:")
For Each cana As CustomAttributeNamedArgument _
In CType(cad.NamedArguments, IEnumerable(Of CustomAttributeNamedArgument))
Console.WriteLine(" MemberInfo: '{0}'", _
cana.MemberInfo)
ShowValueOrArray(cana.TypedValue)
Next
Next
End Sub
Private Shared Sub ShowValueOrArray(ByVal cata As CustomAttributeTypedArgument)
If cata.Value.GetType() Is GetType(ReadOnlyCollection(Of CustomAttributeTypedArgument)) Then
Console.WriteLine(" Array of '{0}':", cata.ArgumentType)
For Each cataElement As CustomAttributeTypedArgument In cata.Value
Console.WriteLine(" Type: '{0}' Value: '{1}'", _
cataElement.ArgumentType, cataElement.Value)
Next
Else
Console.WriteLine(" Type: '{0}' Value: '{1}'", _
cata.ArgumentType, cata.Value)
End If
End Sub
End Class
' This code example produces output similar to the following:
'
'Attributes for assembly: 'source, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'
' [System.Runtime.CompilerServices.CompilationRelaxationsAttribute((Int32)8)]
' Constructor: 'Void .ctor(Int32)'
' Constructor arguments:
' Type: 'System.Int32' Value: '8'
' Named arguments:
' [System.Runtime.CompilerServices.RuntimeCompatibilityAttribute(WrapNonExceptionThrows = True)]
' Constructor: 'Void .ctor()'
' Constructor arguments:
' Named arguments:
' MemberInfo: 'Boolean WrapNonExceptionThrows'
' Type: 'System.Boolean' Value: 'True'
' [ExampleAttribute((ExampleKind)2, Note = "This is a note on the assembly.")]
' Constructor: 'Void .ctor(ExampleKind)'
' Constructor arguments:
' Type: 'ExampleKind' Value: '2'
' Named arguments:
' MemberInfo: 'System.String Note'
' Type: 'System.String' Value: 'This is a note on the assembly.'
'
'Attributes for type: 'Test'
' [ExampleAttribute((ExampleKind)1, new String[3] { "String array argument, line 1", "String array argument, line 2", "String array argument, line 3" }, Note = "This is a note on the class.", Numbers = new Int32[3] { 53, 57, 59 })]
' Constructor: 'Void .ctor(ExampleKind, System.String[])'
' Constructor arguments:
' Type: 'ExampleKind' Value: '1'
' Array of 'System.String[]':
' Type: 'System.String' Value: 'String array argument, line 1'
' Type: 'System.String' Value: 'String array argument, line 2'
' Type: 'System.String' Value: 'String array argument, line 3'
' Named arguments:
' MemberInfo: 'System.String Note'
' Type: 'System.String' Value: 'This is a note on the class.'
' MemberInfo: 'Int32[] Numbers'
' Array of 'System.Int32[]':
' Type: 'System.Int32' Value: '53'
' Type: 'System.Int32' Value: '57'
' Type: 'System.Int32' Value: '59'
'
'Attributes for member: 'Void TestMethod(System.Object)'
' [ExampleAttribute(Note = "This is a note on a method.")]
' Constructor: 'Void .ctor()'
' Constructor arguments:
' Named arguments:
' MemberInfo: 'System.String Note'
' Type: 'System.String' Value: 'This is a note on a method.'
'
'Attributes for parameter: 'System.Object arg'
' [ExampleAttribute()]
' Constructor: 'Void .ctor()'
' Constructor arguments:
' Named arguments:
注釈
型メンバーを表す名前空間のクラスとクラスはすべて からMemberInfo派生するためType、このメソッド オーバーロードは型、入れ子になった型、および型メンバーのSystem.Reflectionカスタム属性データを取得します。
こちらもご覧ください
適用対象
GetCustomAttributes(Module)
ターゲット モジュールに適用されている属性に関するデータを表す CustomAttributeData オブジェクトのリストを戻します。
public:
static System::Collections::Generic::IList<System::Reflection::CustomAttributeData ^> ^ GetCustomAttributes(System::Reflection::Module ^ target);
public static System.Collections.Generic.IList<System.Reflection.CustomAttributeData> GetCustomAttributes (System.Reflection.Module target);
static member GetCustomAttributes : System.Reflection.Module -> System.Collections.Generic.IList<System.Reflection.CustomAttributeData>
Public Shared Function GetCustomAttributes (target As Module) As IList(Of CustomAttributeData)
パラメーター
- target
- Module
取得するカスタム属性データが含まれるモジュール。
戻り値
ターゲット モジュールに適用されている属性に関するデータを表すオブジェクトのリスト。
例外
target
が null
です。
適用対象
GetCustomAttributes(ParameterInfo)
ターゲット パラメーターに適用されている属性に関するデータを表す CustomAttributeData オブジェクトのリストを戻します。
public:
static System::Collections::Generic::IList<System::Reflection::CustomAttributeData ^> ^ GetCustomAttributes(System::Reflection::ParameterInfo ^ target);
public static System.Collections.Generic.IList<System.Reflection.CustomAttributeData> GetCustomAttributes (System.Reflection.ParameterInfo target);
static member GetCustomAttributes : System.Reflection.ParameterInfo -> System.Collections.Generic.IList<System.Reflection.CustomAttributeData>
Public Shared Function GetCustomAttributes (target As ParameterInfo) As IList(Of CustomAttributeData)
パラメーター
- target
- ParameterInfo
取得する属性データが含まれるパラメーター。
戻り値
ターゲット パラメーターに適用されている属性に関するデータを表すオブジェクトのリスト。
例外
target
が null
です。
例
次の例では、4 つのコンストラクターと 4 つのプロパティを持つカスタム属性を定義します。 2 つのプロパティは読み取り専用であり、コンストラクターの位置パラメーターを使用して設定されます。 他の 2 つのプロパティは読み取り/書き込みであり、名前付き引数を使用してのみ設定できます。 1 つの位置指定プロパティは文字列の配列であり、1 つの名前付きプロパティは整数の配列です。
この属性は、アセンブリ、アセンブリで宣言された型、型のメソッド、メソッドのパラメーターに適用されます。 このような場合は、さまざまなコンストラクターが使用されます。 アセンブリを実行すると、それ自体がリフレクションのみのコンテキストに読み込まれて、カスタム属性が表示されます。
型に適用される 属性は、位置引数と名前付き引数の両方を持つ配列プロパティを示しています。
メソッドは GetCustomAttributes 、 で Main()
使用され、テスト メソッドのパラメーターに適用されるカスタム属性を取得します。 の GetCustomAttributes 戻り値が メソッドに ShowAttributeData
渡されます。
using namespace System;
using namespace System::Reflection;
using namespace System::Collections::Generic;
using namespace System::Collections::ObjectModel;
// An enumeration used by the ExampleAttribute class.
public enum class ExampleKind
{
FirstKind, SecondKind, ThirdKind, FourthKind
};
// An example attribute. The attribute can be applied to all
// targets, from assemblies to parameters.
//
[AttributeUsage(AttributeTargets::All)]
public ref class ExampleAttribute: public Attribute
{
private:
// Data for properties.
ExampleKind kindValue;
String^ noteValue;
array<String^>^ arrayStrings;
array<int>^ arrayNumbers;
// Constructors.
void ExampleAttributeInitialize( ExampleKind initKind, array<String^>^ initStrings )
{
kindValue = initKind;
arrayStrings = initStrings;
}
public:
ExampleAttribute()
{
ExampleAttributeInitialize( ExampleKind::FirstKind, nullptr );
}
ExampleAttribute( ExampleKind initKind )
{
ExampleAttributeInitialize( initKind, nullptr );
}
ExampleAttribute( ExampleKind initKind, array<String^>^ initStrings )
{
ExampleAttributeInitialize( initKind, initStrings );
}
// Properties. The Note and Numbers properties must be read/write, so they
// can be used as named parameters.
//
property ExampleKind Kind
{
ExampleKind get()
{
return kindValue;
}
}
property array<String^>^ Strings
{
array<String^>^ get()
{
return arrayStrings;
}
}
property String^ Note
{
String^ get()
{
return noteValue;
}
void set( String^ value )
{
noteValue = value;
}
}
property array<int>^ Numbers
{
array<int>^ get()
{
return arrayNumbers;
}
void set( array<int>^ value )
{
arrayNumbers = value;
}
}
};
// The example attribute is applied to the assembly.
[assembly:Example(ExampleKind::ThirdKind,Note="This is a note on the assembly.")];
// The example attribute is applied to the test class.
//
[Example(ExampleKind::SecondKind,
gcnew array<String^> { "String array argument, line 1",
"String array argument, line 2",
"String array argument, line 3" },
Note="This is a note on the class.",
Numbers = gcnew array<int> { 53, 57, 59 })]
public ref class Test
{
public:
// The example attribute is applied to a method, using the
// parameterless constructor and supplying a named argument.
// The attribute is also applied to the method parameter.
//
[Example(Note="This is a note on a method.")]
void TestMethod( [Example] Object^ arg ){}
// Main() gets objects representing the assembly, the test
// type, the test method, and the method parameter. Custom
// attribute data is displayed for each of these.
//
static void Main()
{
Assembly^ assembly = Assembly::ReflectionOnlyLoad( "Source" );
Type^ t = assembly->GetType( "Test" );
MethodInfo^ m = t->GetMethod( "TestMethod" );
array<ParameterInfo^>^p = m->GetParameters();
Console::WriteLine( "\r\nAttributes for assembly: '{0}'", assembly );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( assembly ) );
Console::WriteLine( "\r\nAttributes for type: '{0}'", t );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( t ) );
Console::WriteLine( "\r\nAttributes for member: '{0}'", m );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( m ) );
Console::WriteLine( "\r\nAttributes for parameter: '{0}'", p );
ShowAttributeData( CustomAttributeData::GetCustomAttributes( p[ 0 ] ) );
}
private:
static void ShowValueOrArray(CustomAttributeTypedArgument^ cata)
{
if (cata->Value->GetType() == ReadOnlyCollection<CustomAttributeTypedArgument>::typeid)
{
Console::WriteLine(" Array of '{0}':", cata->ArgumentType);
for each (CustomAttributeTypedArgument^ cataElement in
(ReadOnlyCollection<CustomAttributeTypedArgument>^) cata->Value)
{
Console::WriteLine(" Type: '{0}' Value: '{1}'",
cataElement->ArgumentType, cataElement->Value);
}
}
else
{
Console::WriteLine( " Type: '{0}' Value: '{1}'",
cata->ArgumentType, cata->Value );
}
}
static void ShowAttributeData( IList< CustomAttributeData^ >^ attributes )
{
for each ( CustomAttributeData^ cad in attributes )
{
Console::WriteLine( " {0}", cad );
Console::WriteLine( " Constructor: '{0}'", cad->Constructor );
Console::WriteLine( " Constructor arguments:" );
for each ( CustomAttributeTypedArgument^ cata in cad->ConstructorArguments )
{
ShowValueOrArray(cata);
}
Console::WriteLine( " Named arguments:" );
for each ( CustomAttributeNamedArgument cana in cad->NamedArguments )
{
Console::WriteLine( " MemberInfo: '{0}'", cana.MemberInfo );
ShowValueOrArray(cana.TypedValue);
}
}
}
};
int main()
{
Test::Main();
}
/* This code example produces output similar to the following:
Attributes for assembly: 'source, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'
[System.Runtime.CompilerServices.CompilationRelaxationsAttribute((Int32)8)]
Constructor: 'Void .ctor(Int32)'
Constructor arguments:
Type: 'System.Int32' Value: '8'
Named arguments:
[System.Runtime.CompilerServices.RuntimeCompatibilityAttribute(WrapNonExceptionThrows = True)]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'Boolean WrapNonExceptionThrows'
Type: 'System.Boolean' Value: 'True'
[ExampleAttribute((ExampleKind)2, Note = "This is a note on the assembly.")]
Constructor: 'Void .ctor(ExampleKind)'
Constructor arguments:
Type: 'ExampleKind' Value: '2'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the assembly.'
Attributes for type: 'Test'
[ExampleAttribute((ExampleKind)1, new String[3] { "String array argument, line 1", "String array argument, line 2", "String array argument, line 3" }, Note = "This is a note on the class.", Numbers = new Int32[3] { 53, 57, 59 })]
Constructor: 'Void .ctor(ExampleKind, System.String[])'
Constructor arguments:
Type: 'ExampleKind' Value: '1'
Array of 'System.String[]':
Type: 'System.String' Value: 'String array argument, line 1'
Type: 'System.String' Value: 'String array argument, line 2'
Type: 'System.String' Value: 'String array argument, line 3'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the class.'
MemberInfo: 'Int32[] Numbers'
Array of 'System.Int32[]':
Type: 'System.Int32' Value: '53'
Type: 'System.Int32' Value: '57'
Type: 'System.Int32' Value: '59'
Attributes for member: 'Void TestMethod(System.Object)'
[ExampleAttribute(Note = "This is a note on a method.")]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on a method.'
Attributes for parameter: 'System.Object arg'
[ExampleAttribute()]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
*/
using System;
using System.Reflection;
using System.Collections.Generic;
using System.Collections.ObjectModel;
// The example attribute is applied to the assembly.
[assembly:Example(ExampleKind.ThirdKind, Note="This is a note on the assembly.")]
// An enumeration used by the ExampleAttribute class.
public enum ExampleKind
{
FirstKind,
SecondKind,
ThirdKind,
FourthKind
};
// An example attribute. The attribute can be applied to all
// targets, from assemblies to parameters.
//
[AttributeUsage(AttributeTargets.All)]
public class ExampleAttribute : Attribute
{
// Data for properties.
private ExampleKind kindValue;
private string noteValue;
private string[] arrayStrings;
private int[] arrayNumbers;
// Constructors. The parameterless constructor (.ctor) calls
// the constructor that specifies ExampleKind and an array of
// strings, and supplies the default values.
//
public ExampleAttribute(ExampleKind initKind, string[] initStrings)
{
kindValue = initKind;
arrayStrings = initStrings;
}
public ExampleAttribute(ExampleKind initKind) : this(initKind, null) {}
public ExampleAttribute() : this(ExampleKind.FirstKind, null) {}
// Properties. The Note and Numbers properties must be read/write, so they
// can be used as named parameters.
//
public ExampleKind Kind { get { return kindValue; }}
public string[] Strings { get { return arrayStrings; }}
public string Note
{
get { return noteValue; }
set { noteValue = value; }
}
public int[] Numbers
{
get { return arrayNumbers; }
set { arrayNumbers = value; }
}
}
// The example attribute is applied to the test class.
//
[Example(ExampleKind.SecondKind,
new string[] { "String array argument, line 1",
"String array argument, line 2",
"String array argument, line 3" },
Note="This is a note on the class.",
Numbers = new int[] { 53, 57, 59 })]
public class Test
{
// The example attribute is applied to a method, using the
// parameterless constructor and supplying a named argument.
// The attribute is also applied to the method parameter.
//
[Example(Note="This is a note on a method.")]
public void TestMethod([Example] object arg) { }
// Main() gets objects representing the assembly, the test
// type, the test method, and the method parameter. Custom
// attribute data is displayed for each of these.
//
public static void Main()
{
Assembly asm = Assembly.ReflectionOnlyLoad("Source");
Type t = asm.GetType("Test");
MethodInfo m = t.GetMethod("TestMethod");
ParameterInfo[] p = m.GetParameters();
Console.WriteLine("\r\nAttributes for assembly: '{0}'", asm);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(asm));
Console.WriteLine("\r\nAttributes for type: '{0}'", t);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(t));
Console.WriteLine("\r\nAttributes for member: '{0}'", m);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(m));
Console.WriteLine("\r\nAttributes for parameter: '{0}'", p);
ShowAttributeData(CustomAttributeData.GetCustomAttributes(p[0]));
}
private static void ShowAttributeData(
IList<CustomAttributeData> attributes)
{
foreach( CustomAttributeData cad in attributes )
{
Console.WriteLine(" {0}", cad);
Console.WriteLine(" Constructor: '{0}'", cad.Constructor);
Console.WriteLine(" Constructor arguments:");
foreach( CustomAttributeTypedArgument cata
in cad.ConstructorArguments )
{
ShowValueOrArray(cata);
}
Console.WriteLine(" Named arguments:");
foreach( CustomAttributeNamedArgument cana
in cad.NamedArguments )
{
Console.WriteLine(" MemberInfo: '{0}'",
cana.MemberInfo);
ShowValueOrArray(cana.TypedValue);
}
}
}
private static void ShowValueOrArray(CustomAttributeTypedArgument cata)
{
if (cata.Value.GetType() == typeof(ReadOnlyCollection<CustomAttributeTypedArgument>))
{
Console.WriteLine(" Array of '{0}':", cata.ArgumentType);
foreach (CustomAttributeTypedArgument cataElement in
(ReadOnlyCollection<CustomAttributeTypedArgument>) cata.Value)
{
Console.WriteLine(" Type: '{0}' Value: '{1}'",
cataElement.ArgumentType, cataElement.Value);
}
}
else
{
Console.WriteLine(" Type: '{0}' Value: '{1}'",
cata.ArgumentType, cata.Value);
}
}
}
/* This code example produces output similar to the following:
Attributes for assembly: 'source, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'
[System.Runtime.CompilerServices.CompilationRelaxationsAttribute((Int32)8)]
Constructor: 'Void .ctor(Int32)'
Constructor arguments:
Type: 'System.Int32' Value: '8'
Named arguments:
[System.Runtime.CompilerServices.RuntimeCompatibilityAttribute(WrapNonExceptionThrows = True)]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'Boolean WrapNonExceptionThrows'
Type: 'System.Boolean' Value: 'True'
[ExampleAttribute((ExampleKind)2, Note = "This is a note on the assembly.")]
Constructor: 'Void .ctor(ExampleKind)'
Constructor arguments:
Type: 'ExampleKind' Value: '2'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the assembly.'
Attributes for type: 'Test'
[ExampleAttribute((ExampleKind)1, new String[3] { "String array argument, line 1", "String array argument, line 2", "String array argument, line 3" }, Note = "This is a note on the class.", Numbers = new Int32[3] { 53, 57, 59 })]
Constructor: 'Void .ctor(ExampleKind, System.String[])'
Constructor arguments:
Type: 'ExampleKind' Value: '1'
Array of 'System.String[]':
Type: 'System.String' Value: 'String array argument, line 1'
Type: 'System.String' Value: 'String array argument, line 2'
Type: 'System.String' Value: 'String array argument, line 3'
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on the class.'
MemberInfo: 'Int32[] Numbers'
Array of 'System.Int32[]':
Type: 'System.Int32' Value: '53'
Type: 'System.Int32' Value: '57'
Type: 'System.Int32' Value: '59'
Attributes for member: 'Void TestMethod(System.Object)'
[ExampleAttribute(Note = "This is a note on a method.")]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
MemberInfo: 'System.String Note'
Type: 'System.String' Value: 'This is a note on a method.'
Attributes for parameter: 'System.Object arg'
[ExampleAttribute()]
Constructor: 'Void .ctor()'
Constructor arguments:
Named arguments:
*/
Imports System.Reflection
Imports System.Collections.Generic
Imports System.Collections.ObjectModel
' The example attribute is applied to the assembly.
<Assembly:Example(ExampleKind.ThirdKind, Note:="This is a note on the assembly.")>
' An enumeration used by the ExampleAttribute class.
Public Enum ExampleKind
FirstKind
SecondKind
ThirdKind
FourthKind
End Enum
' An example attribute. The attribute can be applied to all
' targets, from assemblies to parameters.
'
<AttributeUsage(AttributeTargets.All)> _
Public Class ExampleAttribute
Inherits Attribute
' Data for properties.
Private kindValue As ExampleKind
Private noteValue As String
Private arrayStrings() As String
Private arrayNumbers() As Integer
' Constructors. The parameterless constructor (.ctor) calls
' the constructor that specifies ExampleKind and an array of
' strings, and supplies the default values.
'
Public Sub New(ByVal initKind As ExampleKind, ByVal initStrings() As String)
kindValue = initKind
arrayStrings = initStrings
End Sub
Public Sub New(ByVal initKind As ExampleKind)
Me.New(initKind, Nothing)
End Sub
Public Sub New()
Me.New(ExampleKind.FirstKind, Nothing)
End Sub
' Properties. The Note and Numbers properties must be read/write, so they
' can be used as named parameters.
'
Public ReadOnly Property Kind As ExampleKind
Get
Return kindValue
End Get
End Property
Public ReadOnly Property Strings As String()
Get
Return arrayStrings
End Get
End Property
Public Property Note As String
Get
Return noteValue
End Get
Set
noteValue = value
End Set
End Property
Public Property Numbers As Integer()
Get
Return arrayNumbers
End Get
Set
arrayNumbers = value
End Set
End Property
End Class
' The example attribute is applied to the test class.
'
<Example(ExampleKind.SecondKind, _
New String() { "String array argument, line 1", _
"String array argument, line 2", _
"String array argument, line 3" }, _
Note := "This is a note on the class.", _
Numbers := New Integer() { 53, 57, 59 })> _
Public Class Test
' The example attribute is applied to a method, using the
' parameterless constructor and supplying a named argument.
' The attribute is also applied to the method parameter.
'
<Example(Note:="This is a note on a method.")> _
Public Sub TestMethod(<Example()> ByVal arg As Object)
End Sub
' Sub Main gets objects representing the assembly, the test
' type, the test method, and the method parameter. Custom
' attribute data is displayed for each of these.
'
Public Shared Sub Main()
Dim asm As [Assembly] = Assembly.ReflectionOnlyLoad("source")
Dim t As Type = asm.GetType("Test")
Dim m As MethodInfo = t.GetMethod("TestMethod")
Dim p() As ParameterInfo = m.GetParameters()
Console.WriteLine(vbCrLf & "Attributes for assembly: '{0}'", asm)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(asm))
Console.WriteLine(vbCrLf & "Attributes for type: '{0}'", t)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(t))
Console.WriteLine(vbCrLf & "Attributes for member: '{0}'", m)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(m))
Console.WriteLine(vbCrLf & "Attributes for parameter: '{0}'", p)
ShowAttributeData(CustomAttributeData.GetCustomAttributes(p(0)))
End Sub
Private Shared Sub ShowAttributeData( _
ByVal attributes As IList(Of CustomAttributeData))
For Each cad As CustomAttributeData _
In CType(attributes, IEnumerable(Of CustomAttributeData))
Console.WriteLine(" {0}", cad)
Console.WriteLine(" Constructor: '{0}'", cad.Constructor)
Console.WriteLine(" Constructor arguments:")
For Each cata As CustomAttributeTypedArgument _
In CType(cad.ConstructorArguments, IEnumerable(Of CustomAttributeTypedArgument))
ShowValueOrArray(cata)
Next
Console.WriteLine(" Named arguments:")
For Each cana As CustomAttributeNamedArgument _
In CType(cad.NamedArguments, IEnumerable(Of CustomAttributeNamedArgument))
Console.WriteLine(" MemberInfo: '{0}'", _
cana.MemberInfo)
ShowValueOrArray(cana.TypedValue)
Next
Next
End Sub
Private Shared Sub ShowValueOrArray(ByVal cata As CustomAttributeTypedArgument)
If cata.Value.GetType() Is GetType(ReadOnlyCollection(Of CustomAttributeTypedArgument)) Then
Console.WriteLine(" Array of '{0}':", cata.ArgumentType)
For Each cataElement As CustomAttributeTypedArgument In cata.Value
Console.WriteLine(" Type: '{0}' Value: '{1}'", _
cataElement.ArgumentType, cataElement.Value)
Next
Else
Console.WriteLine(" Type: '{0}' Value: '{1}'", _
cata.ArgumentType, cata.Value)
End If
End Sub
End Class
' This code example produces output similar to the following:
'
'Attributes for assembly: 'source, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null'
' [System.Runtime.CompilerServices.CompilationRelaxationsAttribute((Int32)8)]
' Constructor: 'Void .ctor(Int32)'
' Constructor arguments:
' Type: 'System.Int32' Value: '8'
' Named arguments:
' [System.Runtime.CompilerServices.RuntimeCompatibilityAttribute(WrapNonExceptionThrows = True)]
' Constructor: 'Void .ctor()'
' Constructor arguments:
' Named arguments:
' MemberInfo: 'Boolean WrapNonExceptionThrows'
' Type: 'System.Boolean' Value: 'True'
' [ExampleAttribute((ExampleKind)2, Note = "This is a note on the assembly.")]
' Constructor: 'Void .ctor(ExampleKind)'
' Constructor arguments:
' Type: 'ExampleKind' Value: '2'
' Named arguments:
' MemberInfo: 'System.String Note'
' Type: 'System.String' Value: 'This is a note on the assembly.'
'
'Attributes for type: 'Test'
' [ExampleAttribute((ExampleKind)1, new String[3] { "String array argument, line 1", "String array argument, line 2", "String array argument, line 3" }, Note = "This is a note on the class.", Numbers = new Int32[3] { 53, 57, 59 })]
' Constructor: 'Void .ctor(ExampleKind, System.String[])'
' Constructor arguments:
' Type: 'ExampleKind' Value: '1'
' Array of 'System.String[]':
' Type: 'System.String' Value: 'String array argument, line 1'
' Type: 'System.String' Value: 'String array argument, line 2'
' Type: 'System.String' Value: 'String array argument, line 3'
' Named arguments:
' MemberInfo: 'System.String Note'
' Type: 'System.String' Value: 'This is a note on the class.'
' MemberInfo: 'Int32[] Numbers'
' Array of 'System.Int32[]':
' Type: 'System.Int32' Value: '53'
' Type: 'System.Int32' Value: '57'
' Type: 'System.Int32' Value: '59'
'
'Attributes for member: 'Void TestMethod(System.Object)'
' [ExampleAttribute(Note = "This is a note on a method.")]
' Constructor: 'Void .ctor()'
' Constructor arguments:
' Named arguments:
' MemberInfo: 'System.String Note'
' Type: 'System.String' Value: 'This is a note on a method.'
'
'Attributes for parameter: 'System.Object arg'
' [ExampleAttribute()]
' Constructor: 'Void .ctor()'
' Constructor arguments:
' Named arguments:
注釈
このメソッドは、リフレクションのみのコンテキストで常に使用できる メソッドに代わる方法 GetCustomAttributes を提供します。
こちらもご覧ください
適用対象
.NET