/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
/* Individual objects receive notifications when instance
event handlers are used. */
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 {
int id;
public X(int x) { id = x; }
// This is an instance method that will be used as an event handler.
public void Xhandler() {
Console.WriteLine("Event received by object " + id);
}
}
public class EventDemo2 {
public static void Main() {
MyEvent evt = new MyEvent();
X o1 = new X(1);
X o2 = new X(2);
X o3 = new X(3);
evt.SomeEvent += new MyEventHandler(o1.Xhandler);
evt.SomeEvent += new MyEventHandler(o2.Xhandler);
evt.SomeEvent += new MyEventHandler(o3.Xhandler);
// Fire the event.
evt.OnSomeEvent();
}
}
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