MemberInfo.GetCustomAttributes Methode

Quelle:

MemberInfo.cs

Quelle:

MemberInfo.cs

Quelle:

MemberInfo.cs

public:
 abstract cli::array <System::Object ^> ^ GetCustomAttributes(bool inherit);

public abstract object[] GetCustomAttributes (bool inherit);

abstract member GetCustomAttributes : bool -> obj[]

Public MustOverride Function GetCustomAttributes (inherit As Boolean) As Object()

Parameter

Gibt zurück

Ein Array, das sämtliche auf diesen Member angewendeten benutzerdefinierten Attribute enthält, oder ein Array ohne Elemente, wenn keine Attribute definiert sind.

Implementiert

Ausnahmen

Beispiele

Das folgende Beispiel definiert ein benutzerdefiniertes Attribut und ordnet das Attribut zu MyClass.MyMethod, ruft das Attribut zur Laufzeit ab und zeigt das Ergebnis an.

using namespace System;
using namespace System::Reflection;

// Define a custom attribute with one named parameter.

[AttributeUsage(AttributeTargets::All)]
public ref class MyAttribute: public Attribute
{
private:
   String^ myName;

public:
   MyAttribute( String^ name )
   {
      myName = name;
   }

   property String^ Name 
   {
      String^ get()
      {
         return myName;
      }
   }
};

// Define a class that has the custom attribute associated with one of its members.
public ref class MyClass1
{
public:

   [MyAttribute("This is an example attribute.")]
   void MyMethod( int i )
   {
      return;
   }
};

int main()
{
   try
   {
      // Get the type of MyClass1.
      Type^ myType = MyClass1::typeid;

      // Get the members associated with MyClass1.
      array<MemberInfo^>^myMembers = myType->GetMembers();

      // Display the attributes for each of the members of MyClass1.
      for ( int i = 0; i < myMembers->Length; i++ )
      {
         array<Object^>^myAttributes = myMembers[ i ]->GetCustomAttributes( true );
         if ( myAttributes->Length > 0 )
         {
            Console::WriteLine( "\nThe attributes for the member {0} are: \n", myMembers[ i ] );
            for ( int j = 0; j < myAttributes->Length; j++ )
               Console::WriteLine( "The type of the attribute is {0}.", myAttributes[ j ] );
         }
      }
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "An exception occurred: {0}", e->Message );
   }
}

using System;
using System.Reflection;

// Define a custom attribute with one named parameter.
[AttributeUsage(AttributeTargets.All)]
public class MyAttribute : Attribute
{
    private string myName;
    public MyAttribute(string name)
    {
        myName = name;
    }
    public string Name
    {
        get
        {
            return myName;
        }
    }
}

// Define a class that has the custom attribute associated with one of its members.
public class MyClass1
{
    [MyAttribute("This is an example attribute.")]
    public void MyMethod(int i)
    {
        return;
    }
}

public class MemberInfo_GetCustomAttributes
{
    public static void Main()
    {
        try
        {
            // Get the type of MyClass1.
            Type myType = typeof(MyClass1);
            // Get the members associated with MyClass1.
            MemberInfo[] myMembers = myType.GetMembers();

            // Display the attributes for each of the members of MyClass1.
            for(int i = 0; i < myMembers.Length; i++)
            {
                Object[] myAttributes = myMembers[i].GetCustomAttributes(true);
                if(myAttributes.Length > 0)
                {
                    Console.WriteLine("\nThe attributes for the member {0} are: \n", myMembers[i]);
                    for(int j = 0; j < myAttributes.Length; j++)
                        Console.WriteLine("The type of the attribute is {0}.", myAttributes[j]);
                }
            }
        }
        catch(Exception e)
        {
            Console.WriteLine("An exception occurred: {0}", e.Message);
        }
    }
}

Imports System.Reflection

' Define a custom attribute with one named parameter.
<AttributeUsage(AttributeTargets.All)> Public Class MyAttribute
    Inherits Attribute
    Private myName As String

    Public Sub New(ByVal name As String)
        myName = name
    End Sub

    Public ReadOnly Property Name() As String
        Get
            Return myName
        End Get
    End Property
End Class

' Define a class that has the custom attribute associated with one of its members.
Public Class MyClass1

    <MyAttribute("This is an example attribute.")> Public Sub MyMethod(ByVal i As Integer)
        Return
    End Sub
End Class


Public Class MemberInfo_GetCustomAttributes

    Public Shared Sub Main()
        Try
            ' Get the type of MyClass1.
            Dim myType As Type = GetType(MyClass1)
            ' Get the members associated with MyClass1.
            Dim myMembers As MemberInfo() = myType.GetMembers()

            ' Display the attributes for each of the members of MyClass1.
            Dim i As Integer
            For i = 0 To myMembers.Length - 1
                Dim myAttributes As [Object]() = myMembers(i).GetCustomAttributes(False)
                If myAttributes.Length > 0 Then
                    Console.WriteLine("The attributes for the member {0} are: ", myMembers(i))
                    Dim j As Integer
                    For j = 0 To myAttributes.Length - 1
                        Console.WriteLine("The type of the attribute is: {0}", myAttributes(j))
                    Next j
                End If
            Next i
        Catch e As Exception
            Console.WriteLine("An exception occurred: {0}.", e.Message)
        End Try
    End Sub
End Class

Hinweise

Diese Methode ignoriert den inherit Parameter für Eigenschaften und Ereignisse. Verwenden Sie die entsprechenden Überladungen der Methode, um die Vererbungskette nach Attributen Attribute.GetCustomAttributes für Eigenschaften und Ereignisse zu durchsuchen.

Weitere Informationen

• Object
• CustomAttributeBuilder

Quelle:

MemberInfo.cs

Quelle:

MemberInfo.cs

Quelle:

MemberInfo.cs

public:
 abstract cli::array <System::Object ^> ^ GetCustomAttributes(Type ^ attributeType, bool inherit);

public abstract object[] GetCustomAttributes (Type attributeType, bool inherit);

abstract member GetCustomAttributes : Type * bool -> obj[]

Public MustOverride Function GetCustomAttributes (attributeType As Type, inherit As Boolean) As Object()

Parameter

Gibt zurück

Ein Array aus benutzerdefinierten Attributen, die auf diesen Member angewendet wurden, oder ein Array mit 0 (null) Elementen, wenn keine Attribute angewendet wurden, die attributeType zugewiesen werden können.

Implementiert

Ausnahmen

Beispiele

Im folgenden Beispiel wird eine Klasse mit dem Namen BaseClass definiert, die über zwei nicht geerbte Member verfügt: ein statisches Threadfeld mit dem Namen total und eine nicht CLS-kompatible Methode mit dem Namen MethodA. Eine Klasse namens DerivedClass erbt von BaseClass und überschreibt ihre MethodA Methode. Beachten Sie, dass keine Attribute auf die Member von DerivedClassangewendet werden. Im Beispiel werden die Member von DerivedClass durchlaufen, um zu bestimmen, ob das CLSCompliantAttribute Attribut oder ThreadStaticAttribute auf sie angewendet wurde. Da inherit ist true, durchsucht die -Methode die Vererbungshierarchie von DerivedClass nach dem angegebenen Attribut. Wie die Ausgabe aus dem Beispiel zeigt, ist das total Feld mit dem ThreadStaticAttribute -Attribut versehen, und die MethodA -Methode ist mit dem CLSCompliantAttribute -Attribut versehen.

using System;

public class BaseClass
{
   [ThreadStatic] public int total;

   [CLSCompliant(false)] public virtual uint MethodA()
   {
      return (uint) 100;
   }
}

public class DerivedClass : BaseClass
{
   public override uint MethodA()
   {
      total++;
      return 200;
   }
}

public class Example
{
   public static void Main()
   {
      Type t = typeof(DerivedClass);
      Console.WriteLine("Members of {0}:", t.FullName);
      foreach (var m in t.GetMembers())
      {
         bool hasAttribute = false;
         Console.Write("   {0}: ", m.Name);
         if (m.GetCustomAttributes(typeof(CLSCompliantAttribute), true).Length > 0) {
            Console.Write("CLSCompliant");
            hasAttribute = true;
         }
         if (m.GetCustomAttributes(typeof(ThreadStaticAttribute), true).Length > 0) {
            Console.Write("ThreadStatic");
            hasAttribute = true;
         }
         if (! hasAttribute)
            Console.Write("No attributes");

         Console.WriteLine();
      }
   }
}
// The example displays the following output:
//       Members of DerivedClass:
//          MethodA: CLSCompliant
//          ToString: No attributes
//          Equals: No attributes
//          GetHashCode: No attributes
//          typeof: No attributes
//          .ctor: No attributes
//          total: ThreadStatic

Public Class BaseClass
   <ThreadStatic> Public total As Integer
   
   <CLSCompliant(False)> Public Overridable Function MethodA() As UInt32
      Return CUInt(100)
   End Function
End Class

Public Class DerivedClass : Inherits BaseClass
   Public Overrides Function MethodA() As UInt32
      total += 1
      Return 200
   End Function
End Class

Module Example
   Public Sub Main()
      Dim t As Type = GetType(DerivedClass)
      Console.WriteLine("Members of {0}:", t.FullName)
      For Each m In t.GetMembers()
         Dim hasAttribute As Boolean = False
         Console.Write("   {0}: ", m.Name)
         If m.GetCustomAttributes(GetType(CLSCompliantAttribute), True).Length > 0 Then
            Console.Write("CLSCompliant")
            hasAttribute = True
         End If
         If m.GetCustomAttributes(GetType(ThreadStaticAttribute), True).Length > 0 Then
            Console.Write("ThreadStatic")
            hasAttribute = True
         End If
         If Not hasAttribute Then
            Console.Write("No attributes")
         End If
         Console.WriteLine()
      Next
   End Sub
End Module
' The example displays the following output:
'       Members of DerivedClass:
'          MethodA: CLSCompliant
'          ToString: No attributes
'          Equals: No attributes
'          GetHashCode: No attributes
'          GetType: No attributes
'          .ctor: No attributes
'          total: ThreadStatic

Hinweise

Diese Methode ignoriert den inherit Parameter für Eigenschaften und Ereignisse. Verwenden Sie die entsprechenden Überladungen der Methode, um die Vererbungskette nach Attributen Attribute.GetCustomAttributes für Eigenschaften und Ereignisse zu durchsuchen.