AttributeTargets Enumeration
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
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: SystemAssembly: mscorlib (in mscorlib.dll)
| Member name | Description | |
|---|---|---|
| All | Attribute can be applied to any application element. | |
| Assembly | Attribute can be applied to an assembly. | |
| Class | Attribute can be applied to a class. | |
| Constructor | Attribute can be applied to a constructor. | |
| Delegate | Attribute can be applied to a delegate. | |
| Enum | Attribute can be applied to an enumeration. | |
| Event | Attribute can be applied to an event. | |
| Field | Attribute can be applied to a field. | |
| 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. | |
| Interface | Attribute can be applied to an interface. | |
| Method | Attribute can be applied to a method. | |
| 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. | |
| Parameter | Attribute can be applied to a parameter. | |
| Property | Attribute can be applied to a property. | |
| ReturnValue | Attribute can be applied to a return value. | |
| Struct | Attribute can be applied to a structure; that is, a value type. |
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.
The following example illustrates the application of attributes to various targets.
Note: |
|---|
Visual Basic syntax currently does not support the application of attributes to type parameters. |
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) { } } }
Note: