CustomAttributeTypedArgument CustomAttributeTypedArgument CustomAttributeTypedArgument CustomAttributeTypedArgument Struct

Definição

Representa um argumento de um atributo personalizado no contexto exclusivamente de reflexão, ou um elemento de um argumento de matriz.Represents an argument of a custom attribute in the reflection-only context, or an element of an array argument.

public value class CustomAttributeTypedArgument
[System.Runtime.InteropServices.ComVisible(true)]
[System.Serializable]
public struct CustomAttributeTypedArgument
type CustomAttributeTypedArgument = struct
Public Structure CustomAttributeTypedArgument
Herança
CustomAttributeTypedArgumentCustomAttributeTypedArgumentCustomAttributeTypedArgumentCustomAttributeTypedArgument
Atributos

Exemplos

O exemplo a seguir define um atributo personalizado com quatro construtores e quatro propriedades.The following example defines a custom attribute with four constructors and four properties. Duas das propriedades são somente leitura e são definidas usando os parâmetros posicionais dos construtores.Two of the properties are read-only, and are set by using the positional parameters of the constructors. As outras duas propriedades são leitura/gravação e só podem ser definidas usando argumentos nomeados.The other two properties are read/write, and can be set only by using named arguments. Uma propriedade posicional é uma matriz de cadeias de caracteres e uma propriedade nomeada é uma matriz de inteiros.One positional property is an array of strings, and one named property is an array of integers.

O atributo é aplicado ao assembly, a um tipo declarado no assembly, para um método do tipo e a um parâmetro do método.The attribute is applied to the assembly, to a type declared in the assembly, to a method of the type, and to a parameter of the method. Construtores diferentes são usados nesses casos.Different constructors are used for these cases. Quando executado, o assembly se carrega no contexto somente de reflexão e exibe os atributos personalizados.When executed, the assembly loads itself into the reflection-only context and displays the custom attributes.

O atributo que é aplicado ao tipo demonstra propriedades de matriz, com argumentos posicionais e nomeados.The attribute that is applied to the type demonstrates array properties, with both positional and named arguments.

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:

Comentários

O código que está sendo examinado no contexto somente de reflexão não pode ser executado, portanto nem sempre é possível examinar atributos personalizados criando instâncias deles e, em seguida, examinando suas propriedades, usando Attribute.GetCustomAttributesmétodos MemberInfo.GetCustomAttributescomo, e assim por diante .Code that is being examined in the reflection-only context cannot be executed, so it is not always possible to examine custom attributes by creating instances of them and then examining their properties, using methods like Attribute.GetCustomAttributes, MemberInfo.GetCustomAttributes, and so on. Se o código para o tipo de atributo em si for carregado no contexto somente de reflexão, ele não poderá ser executado.If the code for the attribute type itself is loaded into the reflection-only context, it cannot be executed.

A CustomAttributeNamedArgument estrutura é usada CustomAttributeData pela classe para fornecer acesso ao tipo e ao valor de um argumento posicional especificado para uma instância de atributo Personalizada, sem executar o construtor de atributo.The CustomAttributeNamedArgument structure is used by the CustomAttributeData class to provide access to the type and value of a positional argument specified for a custom attribute instance, without executing the attribute constructor. Ele também fornece acesso ao tipo e ao valor de um argumento nomeado sem executar o código da propriedade correspondente do tipo de atributo personalizado.It also provides access to the type and value of a named argument without executing the code of the corresponding property of the custom attribute type.

Os tipos e valores de todos os argumentos posicionais e nomeados de uma instância de atributo são CustomAttributeTypedArgument fornecidos por estruturas.The types and values of all the positional and named arguments of an attribute instance are provided by CustomAttributeTypedArgument structures. Os atributos posicionais CustomAttributeData.ConstructorArguments retornados pela propriedade são representados diretamente por CustomAttributeTypedArgument estruturas, mas os argumentos CustomAttributeData.NamedArguments nomeados retornados pela propriedade são representados CustomAttributeNamedArgument por estruturas; para obter CustomAttributeTypedArgument o estrutura para um argumento nomeado, use a CustomAttributeNamedArgument.TypedValue propriedade.The positional attributes returned by the CustomAttributeData.ConstructorArguments property are directly represented by CustomAttributeTypedArgument structures, but the named arguments returned by the CustomAttributeData.NamedArguments property are represented by CustomAttributeNamedArgument structures; to get the CustomAttributeTypedArgument structure for a named argument, use the CustomAttributeNamedArgument.TypedValue property.

Se um argumento for uma matriz de valores, a Value propriedade CustomAttributeTypedArgument do que representa o argumento retornará um genérico ReadOnlyCollection<T> de CustomAttributeTypedArgument objetos.If an argument is an array of values, the Value property of the CustomAttributeTypedArgument that represents the argument returns a generic ReadOnlyCollection<T> of CustomAttributeTypedArgument objects. Cada CustomAttributeTypedArgument objeto na coleção representa o elemento correspondente da matriz.Each CustomAttributeTypedArgument object in the collection represents the corresponding element of the array.

Para criar instâncias da CustomAttributeData classe, use o static GetCustomAttributes método de fábrica.To create instances of the CustomAttributeData class, use the staticGetCustomAttributes factory method.

Construtores

CustomAttributeTypedArgument(Object) CustomAttributeTypedArgument(Object) CustomAttributeTypedArgument(Object) CustomAttributeTypedArgument(Object)

Inicializa uma nova instância da classe CustomAttributeTypedArgument com o valor especificado.Initializes a new instance of the CustomAttributeTypedArgument class with the specified value.

CustomAttributeTypedArgument(Type, Object) CustomAttributeTypedArgument(Type, Object) CustomAttributeTypedArgument(Type, Object) CustomAttributeTypedArgument(Type, Object)

Inicializa uma nova instância da classe CustomAttributeTypedArgument com o valor e o tipo especificados.Initializes a new instance of the CustomAttributeTypedArgument class with the specified type and value.

Propriedades

ArgumentType ArgumentType ArgumentType ArgumentType

Obtém o tipo do argumento ou do elemento do argumento da matriz.Gets the type of the argument or of the array argument element.

Value Value Value Value

Obtém o valor do argumento para um argumento simples ou elemento de um argumento de matriz, obtém uma coleção de valores para um argumento de matriz.Gets the value of the argument for a simple argument or for an element of an array argument; gets a collection of values for an array argument.

Métodos

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Indica se essa instância e um objeto especificado são iguais.Indicates whether this instance and a specified object are equal.

GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Retorna o código hash para essa instância.Returns the hash code for this instance.

ToString() ToString() ToString() ToString()

Retorna uma cadeia de caracteres que consiste no nome do argumento, no sinal de igual e uma representação de cadeia de caracteres do valor do argumento.Returns a string consisting of the argument name, the equal sign, and a string representation of the argument value.

Operadores

Equality(CustomAttributeTypedArgument, CustomAttributeTypedArgument) Equality(CustomAttributeTypedArgument, CustomAttributeTypedArgument) Equality(CustomAttributeTypedArgument, CustomAttributeTypedArgument) Equality(CustomAttributeTypedArgument, CustomAttributeTypedArgument)

Testa se duas estruturas CustomAttributeTypedArgument são equivalentes.Tests whether two CustomAttributeTypedArgument structures are equivalent.

Inequality(CustomAttributeTypedArgument, CustomAttributeTypedArgument) Inequality(CustomAttributeTypedArgument, CustomAttributeTypedArgument) Inequality(CustomAttributeTypedArgument, CustomAttributeTypedArgument) Inequality(CustomAttributeTypedArgument, CustomAttributeTypedArgument)

Testa se as duas estruturas CustomAttributeTypedArgument são diferentes.Tests whether two CustomAttributeTypedArgument structures are different.

Aplica-se a

Veja também