Using delegates in C#

Deleagtes could be used in several senarios

extend a classA in a classB

 //Source object

class ClassA
    {
        //Deleagte declaration
        public MyDelegate myDelegate;
    }
   

//Destination object
    class ClassB
    {
        ClassA classA;
        public ClassB()
        {
            // ClassA initailization
            classA = new ClassA();
            //Extend the classA
            classA.myDelegate += new MyDelegate(Method);
            //Call the method
            classA.myDelegate();
           
        }
        public void Method()
        {
            Console.WriteLine("Bonjour");
        }
    }

Events are based on  Delegetes

class CustomEventArgs : EventArgs
    {
        public string Message{get; set;}
        public CustomEventArgs(string Message)
        {
            this.Message = Message;
        }
    }

class Trigger
    {
       
        public delegate void EventHandler(Object sender, CustomEventArgs ce);
       
       
        public event EventHandler TriggerEvent;
       
        public void OnTriggerEvent(string Message)
        {
            TriggerEvent(this, new CustomEventArgs(Message));
        }
    }

To consume this event:

class Program
  {
    static void Main(string[] args)
        {
           
            Trigger trigger = new Trigger();
           
            trigger.TriggerEvent+=new Trigger.EventHandler(trigger_TriggerEvent);
           
            trigger.OnTriggerEvent("Hello");
           
            trigger.OnTriggerEvent("How are you!! ; )");
           Console.Read();
        }
    static void trigger_TriggerEvent(object sender, CustomEventArgs ce)
    {
     Console.WriteLine("Event is triggered and the message is {0}", ce.Message);
    }
}


Delegate are used whithin Threading context as Callback operators those call methods executed within  given threads' contexts

System.Threading.ThreadStart threadStart;
Thread myThread;
void Main
{

threadStart = new ThreadStart(Method);
myThread = new Thread(threadStart);
myThread.Start();
}

static void Method()
     {
         Console.WriteLine("Thread is lunched");
     }

And so many other cases