A delegate is nothing but a reference to a method, along with some parameters and a return type. When a delegate is defined, it can be associated with any instance that provides a compatible signature and a return type of the method. In other terms, delegates can be defined as function pointers in C and C++. However, delegates are type-safe, secure, and object-oriented.
A delegate model follows the observer pattern, which allows the subscriber to register with and receive notifications from the provider. To get a better understanding of the observer pattern, take a look at the references provided at the end of this chapter, in the Further reading section.
A classic example of a delegate is event handlers in a Windows application, which are methods that are invoked by delegates. In the context of events, a delegate is an intermediary between the event source...