22. Delegates

[Note: 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. end note]
A delegate declaration defines a class that is derived from the class
System.Delegate. A delegate instance
encapsulates 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. Given a delegate instance and an appropriate set of
arguments, one can invoke all of that
delegate instance?s methods with that set of arguments.
[Note: 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 (§22.1) with the delegate?s
type. This makes delegates perfectly suited for ?anonymous? invocation. end
note]