AttributeTargets AttributeTargets AttributeTargets AttributeTargets Enum

Definition

Specifies the application elements on which it is valid to apply an attribute.

This enumeration has a FlagsAttribute attribute that allows a bitwise combination of its member values.

public enum class AttributeTargets
[System.Flags]
[System.Runtime.InteropServices.ComVisible(true)]
public enum AttributeTargets
type AttributeTargets = 
Public Enum AttributeTargets
Inheritance
AttributeTargetsAttributeTargetsAttributeTargetsAttributeTargets
Attributes

Fields

All All All All 32767

Attribute can be applied to any application element.

Assembly Assembly Assembly Assembly 1

Attribute can be applied to an assembly.

Class Class Class Class 4

Attribute can be applied to a class.

Constructor Constructor Constructor Constructor 32

Attribute can be applied to a constructor.

Delegate Delegate Delegate Delegate 4096

Attribute can be applied to a delegate.

Enum Enum Enum Enum 16

Attribute can be applied to an enumeration.

Event Event Event Event 512

Attribute can be applied to an event.

Field Field Field Field 256

Attribute can be applied to a field.

GenericParameter GenericParameter GenericParameter GenericParameter 16384

Attribute can be applied to a generic parameter.

Interface Interface Interface Interface 1024

Attribute can be applied to an interface.

Method Method Method Method 64

Attribute can be applied to a method.

Module Module Module Module 2

Attribute can be applied to a module.

Parameter Parameter Parameter Parameter 2048

Attribute can be applied to a parameter.

Property Property Property Property 128

Attribute can be applied to a property.

ReturnValue ReturnValue ReturnValue ReturnValue 8192

Attribute can be applied to a return value.

Struct Struct Struct Struct 8

Attribute can be applied to a structure; that is, a value type.

Examples

The following example illustrates the application of attributes to various targets.

Note

Visual Basic and Visual C++ syntax currently do not support the application of attributes to type parameters.

using namespace System;

namespace AttTargsCS
{

   // This attribute is only valid on a class.

   [AttributeUsage(AttributeTargets::Class)]
   public ref class ClassTargetAttribute: public Attribute{};


   // This attribute is only valid on a method.

   [AttributeUsage(AttributeTargets::Method)]
   public ref class MethodTargetAttribute: public Attribute{};


   // This attribute is only valid on a constructor.

   [AttributeUsage(AttributeTargets::Constructor)]
   public ref class ConstructorTargetAttribute: public Attribute{};


   // This attribute is only valid on a field.

   [AttributeUsage(AttributeTargets::Field)]
   public ref class FieldTargetAttribute: public Attribute{};


   // This attribute is valid on a class or a method.

   [AttributeUsage(AttributeTargets::Class|AttributeTargets::Method)]
   public ref class ClassMethodTargetAttribute: public Attribute{};


   // This attribute is valid on any target.

   [AttributeUsage(AttributeTargets::All)]
   public ref class AllTargetsAttribute: public Attribute{};


   [ClassTarget]
   [ClassMethodTarget]
   [AllTargets]
   public ref class TestClassAttribute
   {
   private:

      [ConstructorTarget]
      [AllTargets]
      TestClassAttribute(){}


   public:

      [MethodTarget]
      [ClassMethodTarget]
      [AllTargets]
      void Method1(){}


      [FieldTarget]
      [AllTargets]
      int myInt;
      static void Main(){}

   };

}

using System;

namespace AttTargsCS {
    // This attribute is only valid on a class.
    [AttributeUsage(AttributeTargets.Class)]
    public class ClassTargetAttribute : Attribute {
    }

    // This attribute is only valid on a method.
    [AttributeUsage(AttributeTargets.Method)]
    public class MethodTargetAttribute : Attribute {
    }

    // This attribute is only valid on a constructor.
    [AttributeUsage(AttributeTargets.Constructor)]
    public class ConstructorTargetAttribute : Attribute {
    }

    // This attribute is only valid on a field.
    [AttributeUsage(AttributeTargets.Field)]
    public class FieldTargetAttribute : Attribute {
    }

    // This attribute is valid on a class or a method.
    [AttributeUsage(AttributeTargets.Class|AttributeTargets.Method)]
    public class ClassMethodTargetAttribute : Attribute {
    }

    // This attribute is valid on a generic type parameter.
    [AttributeUsage(AttributeTargets.GenericParameter)]
    public class GenericParameterTargetAttribute : Attribute {
    }

    // This attribute is valid on any target.
    [AttributeUsage(AttributeTargets.All)]
    public class AllTargetsAttribute : Attribute {
    }

    [ClassTarget]
    [ClassMethodTarget]
    [AllTargets]
    public class TestClassAttribute {
        [ConstructorTarget]
        [AllTargets]
        TestClassAttribute() {
        }

        [MethodTarget]
        [ClassMethodTarget]
        [AllTargets]
        public void Method1() {
        }

        [FieldTarget]
        [AllTargets]
        public int myInt;

        public void GenericMethod<
            [GenericParameterTarget, AllTargets] T>(T x) {
        }

        static void Main(string[] args) {
        }
    }
}
Imports System

Module DemoModule
	' This attribute is only valid on a class.
	<AttributeUsage(AttributeTargets.Class)> _
	Public Class ClassTargetAttribute
        Inherits Attribute
	End Class

	' This attribute is only valid on a method.
	<AttributeUsage(AttributeTargets.Method)> _
	Public Class MethodTargetAttribute
        Inherits Attribute
	End Class

	' This attribute is only valid on a constructor.
	<AttributeUsage(AttributeTargets.Constructor)> _
	Public Class ConstructorTargetAttribute 
        Inherits Attribute
	End Class

	' This attribute is only valid on a field.
	<AttributeUsage(AttributeTargets.Field)> _
	Public Class FieldTargetAttribute 
        Inherits Attribute
	End Class

	' This attribute is valid on a class or a method.
	<AttributeUsage(AttributeTargets.Class Or AttributeTargets.Method)> _
	Public Class ClassMethodTargetAttribute 
        Inherits Attribute
	End Class

	' This attribute is valid on any target.
	<AttributeUsage(AttributeTargets.All)> _
	Public Class AllTargetsAttribute 
        Inherits Attribute
	End Class

	<ClassTarget, _
	ClassMethodTarget, _
	AllTargets> _
	Public Class TestClassAttribute
		<ConstructorTarget, _
		AllTargets> _
		Public Sub New
		End Sub

		<MethodTarget, _
		ClassMethodTarget, _
		AllTargets> _
		Public Sub Method1()
		End Sub

		<FieldTarget, _
		AllTargets> _
		Public myInt as Integer
	End Class

	Sub Main()
	End Sub
End Module

Remarks

The AttributeUsageAttribute class uses this enumeration to specify the kind of element on which it is valid to apply an attribute.

AttributeTargets enumeration values can be combined with a bitwise OR operation to get the preferred combination.

Applies to

See Also