Check out example codes for "why events are usefull in c#". It will help you in understanding the concepts better.

Code Example 1

using System;

namespace SampleApp {
   public delegate string MyDel(string str);
	
   class EventProgram {
      event MyDel MyEvent;
		
      public EventProgram() {
         this.MyEvent += new MyDel(this.WelcomeUser);
      }
      public string WelcomeUser(string username) {
         return "Welcome " + username;
      }
      static void Main(string[] args) {
         EventProgram obj1 = new EventProgram();
         string result = obj1.MyEvent("Tutorials Point");
         Console.WriteLine(result);
      }
   }
}

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