using System;

public class Program

{

    public static void Main()

    {

            Derived1 P1 = new Derived1();

            P1.InvokeEvent();

            Derived2 P2 = new Derived2();

            P2.InvokeEvent();

    }

     partial class Base

    {

        protected event EventHandler Handler;

​

        public void InvokeEvent()

        {

            if (Handler != null)

                Handler.Invoke(this, null);

        }

    }

​

    partial class Derived1: Base

    { 

    }

​

    partial class Derived2: Base 

    {

        public Derived2()

        {

            Handler += myMethod;

        }

​

        protected void myMethod(object sender, EventArgs e)

        {

            Console.WriteLine("myMethod");            

        }

    }

}