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CustomAttributeTypedArgument Estructura

  • Referencia

Definición

Espacio de nombres:
System.Reflection
Ensamblado:
System.Reflection.dll
Ensamblado:
System.Runtime.dll
Ensamblado:
mscorlib.dll
Ensamblado:
netstandard.dll
Source:
CustomAttributeTypedArgument.cs
Source:
CustomAttributeTypedArgument.cs
Source:
CustomAttributeTypedArgument.cs

Representa un argumento de un atributo personalizado en el contexto de solo reflexión o un elemento de un argumento de matriz.

public value class CustomAttributeTypedArgument
public value class CustomAttributeTypedArgument : IEquatable<System::Reflection::CustomAttributeTypedArgument>
public struct CustomAttributeTypedArgument
public readonly struct CustomAttributeTypedArgument
public readonly struct CustomAttributeTypedArgument : IEquatable<System.Reflection.CustomAttributeTypedArgument>
[System.Runtime.InteropServices.ComVisible(true)]
[System.Serializable]
public struct CustomAttributeTypedArgument
type CustomAttributeTypedArgument = struct
[<System.Runtime.InteropServices.ComVisible(true)>]
[<System.Serializable>]
type CustomAttributeTypedArgument = struct
Public Structure CustomAttributeTypedArgument
Public Structure CustomAttributeTypedArgument
Implements IEquatable(Of CustomAttributeTypedArgument)
Herencia
Object
ValueType
CustomAttributeTypedArgument
Atributos
ComVisibleAttribute SerializableAttribute
Implementaciones
IEquatable<CustomAttributeTypedArgument>

Ejemplos

En el ejemplo siguiente se define un atributo personalizado con cuatro constructores y cuatro propiedades. Dos de las propiedades son de solo lectura y se establecen mediante los parámetros posicionales de los constructores. Las otras dos propiedades son de lectura y escritura y solo se pueden establecer mediante argumentos con nombre. Una propiedad posicional es una matriz de cadenas y una propiedad con nombre es una matriz de enteros.

El atributo se aplica al ensamblado, a un tipo declarado en el ensamblado, a un método del tipo y a un parámetro del método . Se usan constructores diferentes para estos casos. Cuando se ejecuta, el ensamblado se carga en el contexto de solo reflexión y muestra los atributos personalizados.

El atributo que se aplica al tipo muestra las propiedades de la matriz, con argumentos posicionales y con nombre.

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:

Comentarios

No se puede ejecutar el código que se está examinando en el contexto de solo reflexión, por lo que no siempre es posible examinar atributos personalizados mediante la creación de instancias de ellos y, a continuación, examinar sus propiedades, mediante métodos como Attribute.GetCustomAttributes, MemberInfo.GetCustomAttributes, etc. Si el código del propio tipo de atributo se carga en el contexto de solo reflexión, no se puede ejecutar.

La clase CustomAttributeData usa la estructura CustomAttributeNamedArgument para proporcionar acceso al tipo y el valor de un argumento posicional especificado para una instancia de atributo personalizado, sin ejecutar el constructor de atributos. También proporciona acceso al tipo y el valor de un argumento con nombre sin ejecutar el código de la propiedad correspondiente del tipo de atributo personalizado.

Las estructuras de CustomAttributeTypedArgument proporcionan los tipos y valores de todos los argumentos posicionales y con nombre de una instancia de atributo. Los atributos posicionales devueltos por la propiedad CustomAttributeData.ConstructorArguments se representan directamente mediante estructuras CustomAttributeTypedArgument, pero los argumentos con nombre devueltos por la propiedad CustomAttributeData.NamedArguments se representan mediante estructuras CustomAttributeNamedArgument; para obtener la estructura CustomAttributeTypedArgument de un argumento con nombre, use la propiedad CustomAttributeNamedArgument.TypedValue.

Si un argumento es una matriz de valores, la propiedad Value del CustomAttributeTypedArgument que representa el argumento devuelve un ReadOnlyCollection<T> genérico de CustomAttributeTypedArgument objetos. Cada objeto CustomAttributeTypedArgument de la colección representa el elemento correspondiente de la matriz.

Para crear instancias de la clase CustomAttributeData, use el método staticGetCustomAttributes factory.

Constructores

CustomAttributeTypedArgument(Object)

Inicializa una nueva instancia de la clase CustomAttributeTypedArgument con el valor especificado.
CustomAttributeTypedArgument(Type, Object)

Inicializa una nueva instancia de la clase CustomAttributeTypedArgument con el tipo y el valor especificados.

Propiedades

ArgumentType

Obtiene el tipo del argumento o del elemento de argumento de matriz.
Value

Obtiene el valor del argumento para un argumento simple o para un elemento de un argumento de matriz; obtiene una colección de valores para un argumento de matriz.

Métodos

Equals(CustomAttributeTypedArgument)

Indica si la instancia actual es igual a otra instancia del mismo tipo.
Equals(Object)

Indica si esta instancia y un objeto especificado son iguales.
GetHashCode()

Devuelve el código hash de esta instancia.
ToString()

Devuelve una cadena que consta del nombre del argumento, el signo igual y una representación de cadena del valor del argumento.

Operadores

Equality(CustomAttributeTypedArgument, CustomAttributeTypedArgument)

Comprueba si dos estructuras CustomAttributeTypedArgument son equivalentes.
Inequality(CustomAttributeTypedArgument, CustomAttributeTypedArgument)

Comprueba si dos estructuras CustomAttributeTypedArgument son diferentes.

Se aplica a

Consulte también