Answers for "delegates and events in c#"

why events are usefull in c#

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);
      }
   }
}

delegates and events in c#

public delegate T add<T>(T param1, T param2); // generic delegate

class Program
{
    static void Main(string[] args)
    {
        add<int> sum = Sum;
        Console.WriteLine(sum(10, 20));

        add<string> con = Concat;
        Console.WriteLine(con("Hello ","World!!"));
    }

    public static int Sum(int val1, int val2)
    {
        return val1 + val2;
    }

    public static string Concat(string str1, string str2)
    {
        return str1 + str2;
    }
}