using System;

​

​

namespace eventHandling

{       

        public delegate void MyHandler1(object sender, MyEventArgs e);

        public delegate void MyHandler2(object sender, MyEventArgs e);

        public class A

        {

            public const string m_id = "Class A";

            public void OnHandler1(object sender, MyEventArgs e)

            {

                Console.WriteLine("I am in OnHandler1 and MyEventArgs is {0}", e.m_id);

            }

            public void OnHandler2(object sender, MyEventArgs e)

            {

                Console.WriteLine("I am in OnHandler2 and MyEventArgs is {0}", e.m_id);

            }

            public A(B b)

            {

                MyHandler1 d1 = new MyHandler1(OnHandler1);

                MyHandler2 d2 = new MyHandler2(OnHandler2);b.Event1 += d1;b.Event2 += d2;

            }

        }

        public class B

        {

            public event MyHandler1 Event1;

            public event MyHandler2 Event2;

            public void FireEvent1(MyEventArgs e)

            {

                if (Event1 != null)

                {

                    Event1(this, e);

                }

            }

            public void FireEvent2(MyEventArgs e)

            {

                if (Event2 != null)

                {

                    Event2(this, e);

                }

            }

        }

        public class MyEventArgs : EventArgs

        {

            public string m_id;

        }

            public class Driver

        {

            public static void Main()

            {

                B b = new B();

                A a = new A(b);

                MyEventArgs e1 = new MyEventArgs();

                MyEventArgs e2 = new MyEventArgs();

                e1.m_id = "Event args for event 1";

                e2.m_id = "Event args for event 2";

                b.FireEvent1(e1);b.FireEvent2(e2);

            }

        }

}

​

//Step 1 Create Delegates

//Step 2 Create event handler methods

//Step 3 create delegates, plug in the handler and register with the object that will fire the events

//Step 4 Calls the encapsulated methods through the delegates (fires events)

//base class for class .

//that contains event data and provides a value to use for events that do not include event data