Visual Basic® 2010 Unleashed

Understanding Delegates

Delegates are type safe function pointers. The main difference between classic function pointers (such as C++ pointers) and delegates is that function pointers can point anywhere, and this can be dangerous, whereas delegates can point only to those methods that respect delegates’ signatures. Delegates hold a reference to a procedure (its address) and enable applications to invoke different methods at runtime, but such methods must adhere to the delegate signature; moreover, delegates enable invoking a method from another object. This is important according to the main purpose of delegates, which is offering an infrastructure for handling events.

Where are Delegates Used?

Generally delegates are used in event handling ...