通过事件可以订阅发布者的消息，存在异步问题，即如何让订阅者不影响发布者的执行，只是单纯的获取发布者的数据信息。
以下代码完全取自张子阳博客
- 发布者
1 public class Publisher
2 {
3 //定义事件
4 public event EventHandler MyEvent;
5 public void DoSomething()
6 {
7 Console.WriteLine("DoSomething incoked!");
8
9 if (MyEvent != null)
10 {
11 //获取多播委托的调用列表
12 Delegate[] delArray = MyEvent.GetInvocationList();
13 //异步执行委托
14 foreach(Delegate del in delArray)
15 {
16 EventHandler method = (EventHandler)del;
17 method.BeginInvoke(null, EventArgs.Empty, null, null);
18 }
19 }
20 }
21 }
- 订阅者
1 //第一个订阅者
2 public class Subscriber1
3 {
4 public void OnEvent(object sender, EventArgs e)
5 {
6 Thread.Sleep(TimeSpan.FromSeconds(3));
7 Console.WriteLine("Waited for 5 seconds, subscriber1 invoked!");
8 }
9 }
10 //第二个订阅者
11 public class Subscriber2
12 {
13 public void OnEvent(object sender, EventArgs e)
14 {
15 //throw new Exception("Subscriber2 Failed");
16 Console.WriteLine("Waited for 0 seconds, subscriber2 invoked!");
17 }
18 }
19 //第三个订阅者
20 public class Subscriber3
21 {
22 public void OnEvent(object sender, EventArgs e)
23 {
24 Thread.Sleep(TimeSpan.FromSeconds(2));
25 Console.WriteLine("Waited for 3 seconds, subscriber3 invoked!");
26 }
27 }
- Main函数：
1 static void Main(string[] args)
2 {
3 Publisher pub = new Publisher();
4 pub.MyEvent += (new Subscriber1()).OnEvent;
5 pub.MyEvent += (new Subscriber2()).OnEvent;
6 pub.MyEvent += (new Subscriber3()).OnEvent;
7
8 pub.DoSomething();
9
10 Console.WriteLine("control back to client!
");
11 Console.ReadLine();
12 }
输出结果：
