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FieldInfo.FieldHandle-Eigenschaft

Ruft ein RuntimeFieldHandle ab, das das Handle für die interne Metadatendarstellung eines Felds darstellt.

Namespace: System.Reflection
Assembly: mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public MustOverride ReadOnly Property FieldHandle As RuntimeFieldHandle
'Usage
Dim instance As FieldInfo
Dim value As RuntimeFieldHandle

value = instance.FieldHandle
public abstract RuntimeFieldHandle FieldHandle { get; }
public:
virtual property RuntimeFieldHandle FieldHandle {
    RuntimeFieldHandle get () abstract;
}
/** @property */
public abstract RuntimeFieldHandle get_FieldHandle ()
public abstract function get FieldHandle () : RuntimeFieldHandle

Eigenschaftenwert

Ein Handle für die interne Metadatendarstellung eines Felds.

Hinweise

Die Handles sind nur in der Anwendungsdomäne gültig, in der sie angefordert wurden.

Beispiel

Im folgenden Beispiel werden die Feldinformationen aus MyClass.MyField abgerufen, und es wird das Feld angezeigt, das dem Feldhandle zugeordnet ist.

Imports System
Imports System.Reflection
Imports Microsoft.VisualBasic

Public Class [MyClass]
    Public MyField As String = "Microsoft"
End Class '[MyClass]

Public Class FieldInfo_FieldHandle
    Public Shared Sub Main()
        Dim [myClass] As New [MyClass]()
        ' Get the type of MyClass.
        Dim myType As Type = GetType([MyClass])
        Try
            ' Get the field information of MyField.
            Dim myFieldInfo As FieldInfo = myType.GetField("MyField", BindingFlags.Public Or BindingFlags.Instance)

            ' Determine whether or not the FieldInfo object is null.
            If Not (myFieldInfo Is Nothing) Then
                ' Get the handle for the field.
                Dim myFieldHandle As RuntimeFieldHandle = myFieldInfo.FieldHandle

                DisplayFieldHandle(myFieldHandle)
            Else
                Console.WriteLine("The myFieldInfo object is null.")
            End If
        Catch e As Exception
            Console.WriteLine(" Exception: {0}", e.Message.ToString())
        End Try
    End Sub 'Main

    Public Shared Sub DisplayFieldHandle(ByVal myFieldHandle As RuntimeFieldHandle)
        ' Get the type from the handle.
        Dim myField As FieldInfo = FieldInfo.GetFieldFromHandle(myFieldHandle)
        ' Display the type.
        Console.WriteLine(ControlChars.Cr + "Displaying the field from the handle." + ControlChars.Cr)
        Console.WriteLine("The type is {0}.", myField.ToString())
    End Sub 'DisplayFieldHandle
End Class 'FieldInfo_FieldHandle
using System;
using System.Reflection;
  
public class MyClass
{
    public string MyField = "Microsoft";
}

public class FieldInfo_FieldHandle
{
    public static void Main()
    {
    
        MyClass myClass =new MyClass();

        // Get the type of MyClass.
        Type myType = typeof(MyClass);

        try
        {
            // Get the field information of MyField.
            FieldInfo myFieldInfo = myType.GetField("MyField", BindingFlags.Public 
                | BindingFlags.Instance);
      
            // Determine whether or not the FieldInfo object is null.
            if(myFieldInfo!=null)
            {
                // Get the handle for the field.
                RuntimeFieldHandle myFieldHandle=myFieldInfo.FieldHandle;

                DisplayFieldHandle(myFieldHandle);
            }
            else
            {
                Console.WriteLine("The myFieldInfo object is null.");
            }
        }  
        catch(Exception e)
        {
            Console.WriteLine("Exception: {0}", e.Message);
        }
    }

    public static void DisplayFieldHandle(RuntimeFieldHandle myFieldHandle)
    {
        // Get the type from the handle.
        FieldInfo myField = FieldInfo.GetFieldFromHandle(myFieldHandle);      
      
        // Display the type.
        Console.WriteLine("\nDisplaying the field from the handle.\n");
        Console.WriteLine("The type is {0}.", myField.ToString());
    }
}
using namespace System;
using namespace System::Reflection;

public ref class MyClass
{
public:
   String^ MyField;
};

void DisplayFieldHandle( RuntimeFieldHandle myFieldHandle )
{
   // Get the type from the handle.
   FieldInfo^ myField = FieldInfo::GetFieldFromHandle( myFieldHandle );

   // Display the type.
   Console::WriteLine( "\nDisplaying the field from the handle.\n" );
   Console::WriteLine( "The type is {0}.", myField );
}

int main()
{
   MyClass^ myClass = gcnew MyClass;

   // Get the type of MyClass.
   Type^ myType = MyClass::typeid;
   try
   {
      // Get the field information of MyField.
      FieldInfo^ myFieldInfo = myType->GetField( "MyField", static_cast<BindingFlags>(BindingFlags::Public | BindingFlags::Instance) );

      // Determine whether or not the FieldInfo Object* is 0.
      if ( myFieldInfo != nullptr )
      {
         // Get the handle for the field.
         RuntimeFieldHandle myFieldHandle = myFieldInfo->FieldHandle;
         DisplayFieldHandle( myFieldHandle );
      }
      else
      {
         Console::WriteLine( "The myFieldInfo Object* is 0." );
      }
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "Exception: {0}", e->Message );
   }
}
import System.*;
import System.Reflection.*;

public class MyClass
{
   public String myField = "Microsoft";
} //MyClass

public class FieldInfoFieldHandle
{
    public static void main(String[] args)
    {
        MyClass myClass = new MyClass();

        // Get the type of MyClass.
        Type myType = MyClass.class.ToType();

        try {
            // Get the field information of myField.
            FieldInfo myFieldInfo = myType.GetField("myField", 
                BindingFlags.Public | BindingFlags.Instance);

            // Determine whether or not the FieldInfo object is null.
            if (myFieldInfo != null) {
                // Get the handle for the field.
                RuntimeFieldHandle myFieldHandle = myFieldInfo.
                    get_FieldHandle();
                DisplayFieldHandle(myFieldHandle);
            }
            else {
                Console.WriteLine("The myFieldInfo object is null.");
            }
        }
        catch (System.Exception e) {
                Console.WriteLine("Exception: {0}", e.get_Message());
        }
    } //main

    public static void DisplayFieldHandle(RuntimeFieldHandle myFieldHandle)
    {
        // Get the type from the handle.
        FieldInfo myField = FieldInfo.GetFieldFromHandle(myFieldHandle);

        // Display the type.
        Console.WriteLine("\nDisplaying the field from the handle.\n");
        Console.WriteLine("The type is {0}.", myField.ToString());
    } //DisplayFieldHandle
} //FieldInfoFieldHandle

Plattformen

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile für Pocket PC, Windows Mobile für Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 2.0, 1.1, 1.0

.NET Compact Framework

Unterstützt in: 2.0, 1.0

Siehe auch

Referenz

FieldInfo-Klasse
FieldInfo-Member
System.Reflection-Namespace