An event multicast demonstration : delegate Event « Language Basics « C# / C Sharp
An event multicast demonstration
/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// An event multicast demonstration.
using System;
// Declare a delegate for an event.
delegate void MyEventHandler();
// Declare an event class.
class MyEvent {
public event MyEventHandler SomeEvent;
// This is called to fire the event.
public void OnSomeEvent() {
if(SomeEvent != null)
SomeEvent();
}
}
class X {
public void Xhandler() {
Console.WriteLine("Event received by X object");
}
}
class Y {
public void Yhandler() {
Console.WriteLine("Event received by Y object");
}
}
public class EventDemo1 {
static void handler() {
Console.WriteLine("Event received by EventDemo");
}
public static void Main() {
MyEvent evt = new MyEvent();
X xOb = new X();
Y yOb = new Y();
// Add handlers to the event list.
evt.SomeEvent += new MyEventHandler(handler);
evt.SomeEvent += new MyEventHandler(xOb.Xhandler);
evt.SomeEvent += new MyEventHandler(yOb.Yhandler);
// Fire the event.
evt.OnSomeEvent();
Console.WriteLine();
// Remove a handler.
evt.SomeEvent -= new MyEventHandler(xOb.Xhandler);
evt.OnSomeEvent();
}
}
