ExtensionAttribute Class
Indicates that a method is an extension method, or that a class or assembly contains extension methods.
Namespace: System.Runtime.CompilerServices
Assembly: mscorlib (in mscorlib.dll)
The ExtensionAttribute type exposes the following members.
| Name | Description | |
|---|---|---|
  | Equals | Infrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.) |
| GetHashCode | Returns the hash code for this instance. (Inherited from Attribute.) |
| GetType | Gets the Type of the current instance. (Inherited from Object.) |
| IsDefaultAttribute | When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute.) |
| Match | When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.) |
| ToString | Returns a string that represents the current object. (Inherited from Object.) |
| Name | Description | |
|---|---|---|
| _Attribute.GetIDsOfNames | Maps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.) |
| _Attribute.GetTypeInfo | Retrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.) |
| _Attribute.GetTypeInfoCount | Retrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.) |
| _Attribute.Invoke | Provides access to properties and methods exposed by an object. (Inherited from Attribute.) |
In Visual Basic, you should use this attribute to create an extension method. For more information, see Extension Methods (Visual Basic).
In C#, you do not need to use this attribute; you should use the this (C# Reference) modifier for the first parameter to create an extension method. The compiler automatically emits ExtensionAttribute for extension methods. For more information, see Extension Methods (C# Programming Guide).
If you are writing a compiler that supports extension methods, your compiler should emit this attribute on each extension method and on each class and assembly that contains one or more extension methods.
