Nilay: Simple Example of Delegate and When to Use

Introduction:

A delegate is a class that can hold a reference to a method. Unlike other classes, a delegate class has a signature, and it can hold references only to methods that match its signature. A delegate is thus equivalent to a type-safe function pointer or a callback

The signature of a single cast delegate is shown below:

delegate result-type identifier ([parameters]);

Where:

result-type: The result type, which matches the return type of the function.
identifier: The delegate name.
Parameters: The Parameters, which the function takes.

Examples:

Following declaration define delegate name Add Pointer which will encapsulate any method that takes two objects as parameter and return an int.

When to Use:

· I explained with following simple scenario I have class Called ClsMaths. it basically contain four method Add, Substract, Division and Multiplication. If suppose I have to call four method in Cls Maths class. with following example we can get it.

· Instead creating object every time new method will be added we can create pointer and pointer with matching argument point to ClsMaths method. So we can avoid heavy coupling between ClsMaths and UI code.

· For your understanding I have created simple application. With help of operation we can get result either it would be addition, subtract, Multiplication or Division.