Was this page helpful?
Your feedback about this content is important. Let us know what you think.
Additional feedback?
1500 characters remaining
15. Delegates

15. Delegates

Visual Studio .NET 2003

Delegates enable scenarios that other languages — such as C++, Pascal, and Modula — have addressed with function pointers. Unlike C++ function pointers, however, delegates are fully object oriented, and unlike C++ pointers to member functions, delegates encapsulate both an object instance and a method.

A delegate declaration defines a class that is derived from the class System.Delegate. A delegate instance encapsulates an invocation list, which is a list one or more methods, each of which is referred to as a callable entity. For instance methods, a callable entity consists of an instance and a method on that instance. For static methods, a callable entity consists of just a method. Invoking a delegate instance with an appropriate set of arguments causes each of the delegate's callable entities to be invoked with the given set of arguments.

An interesting and useful property of a delegate instance is that it does not know or care about the classes of the methods it encapsulates; all that matters is that those methods be compatible (Section 15.1) with the delegate's type. This makes delegates perfectly suited for "anonymous" invocation.

Show:
© 2015 Microsoft