Part 36 - C# Tutorial - Delegates

A delegate is a type safe function pointer.That is, they hold reference(Pointer) to a function. 


The signature of the delegate must match the signature of the function, the delegate points to, otherwise you get a compiler error. This is the reason delegates are called as type safe function pointers.


A Delegate is similar to a class. You can create an instance of it, and when you do so, you pass in the function name as a parameter to the delegate constructor, and it is to this function the delegate will point to.


Tip to remember delegate syntax: Delegates syntax look very much similar to a method with a delegate keyword.


Sample Delegate Program:


using System;


// Delegate Declaration. 
public delegate void HelloFunctionDelegate(string Message);


class Pragim
{
    public static void Main()
    {
        // Create the instance of the delegate and pass in the function
        // name as the parameter to the constructor. The passed in
        // function signature must match the signature of the delegate
        HelloFunctionDelegate del = new HelloFunctionDelegate(Hello);
        // Invoke the delegate, which will invoke the method
        del("Hello from Delegte");
    }


    public static void Hello(string strMessge)
    {
        Console.WriteLine(strMessge);
    }
}

Part 36 - C# Tutorial - Delegates