1 out of 1 rated this helpful - Rate this topic

AttributeTargets Enumeration

.NET Framework 4

Other Versions

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.

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

Syntax

C++

Copy

[SerializableAttribute]
[FlagsAttribute]
[ComVisibleAttribute(true)]
public enum AttributeTargets

Members

	Member name	Description
	Assembly	Attribute can be applied to an assembly.
	Module	Attribute can be applied to a module. Note Module refers to a portable executable file (.dll or.exe) and not a Visual Basic standard module.
	Class	Attribute can be applied to a class.
	Struct	Attribute can be applied to a structure; that is, a value type.
	Enum	Attribute can be applied to an enumeration.
	Constructor	Attribute can be applied to a constructor.
	Method	Attribute can be applied to a method.
	Property	Attribute can be applied to a property.
	Field	Attribute can be applied to a field.
	Event	Attribute can be applied to an event.
	Interface	Attribute can be applied to an interface.
	Parameter	Attribute can be applied to a parameter.
	Delegate	Attribute can be applied to a delegate.
	ReturnValue	Attribute can be applied to a return value.
	GenericParameter	Attribute can be applied to a generic parameter. Note Currently, this attribute can be applied only in C#, Microsoft intermediate language (MSIL), and emitted code.
	All	Attribute can be applied to any application element.

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.

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.

C++

Copy


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) {
        }
    }
}

Version Information

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Platforms

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Reference

System Namespace

AttributeUsageAttribute

Did you find this helpful? Yes No

Not accurate

Not enough depth

Need more code examples

(1500 characters remaining)

Community Content Add

FAQ

Extra info

Some additional notes:
AttributeTargets.Field also applies to members of an enum type (individual named constants of the enum type)
AttributeTargets.Property also applies to C# indexers
AttributeTargets.Method also applies to accessors (getters and setters) of a property or indexer
AttributeTargets.Parameter also applies to the implicit last parametre ("value") of a property/indexer setter
...

/JeppeSN

History

10/13/2011
JeppeSN1