备忘，Sl中委托使用两种方法

这些日子使用委托的时候很不顺，于是认真的看了几篇文章，然后写了个小demo，于是效果就出来了。

delegate可以多播，有两种方法实现

1、使用同一对象，接收消息

代码：

TestA 类中的委托

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public class TestA     {         //定义委托 计算点到直线的距离         public delegate void SendMessageAEventHandler(object sender, object obj);         //定义事件         public event SendMessageAEventHandler SendMessageEventA;           public TestA() {             this.SendMessageEventA +=new SendMessageAEventHandler(TestA_SendMessageEventA);         }           void TestA_SendMessageEventA(object sender, object obj) {             MessageBox.Show("A TestA  " + obj.ToString());         }           public void SendMessageATest(string msg) {               SendMessageAEventHandler handle = SendMessageEventA;               if (handle != null) {                 handle(this, msg);             }         }     }

在MainPage中使用

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void MainPage_Loaded(Object sender, RoutedEventArgs e) {              ta = new TestA();             ta.SendMessageEventA +=new TestA.SendMessageAEventHandler(ta_SendMessageEventA);         } //接收 void ta_SendMessageEventA(object sender, object obj) {             MessageBox.Show("A MainPageTestA  "+obj.ToString());         } //发送  private void button2_Click(object sender, RoutedEventArgs e)         {             ta.SendMessageATest(this.textBox2.Text);         }

在Test中接收

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public Test(MainPage mainPage,TestA t) {            mainPage.SendMessageEvent +=new MainPage.SendMessageEventHandler(mainPage_SendMessageEvent);                          t.SendMessageEventA +=new TestA.SendMessageAEventHandler(ta_SendMessageEventA);             TestB.SendMessageEventB+=new TestB.SendMessageBEventHandler(TestB_SendMessageEventB);         }   void ta_SendMessageEventA(object sender, object obj) {             MessageBox.Show("A TestA " + obj.ToString());         }

结论表示，通过按钮事件发送一个消息，MainPage 和Test 中都可以接收

2、使用静态的事件定义接收

TestB中定义静态的委托事件

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public class TestB     {          //定义委托 计算点到直线的距离         public  delegate void SendMessageBEventHandler(object sender, object obj);         //定义事件         public static event SendMessageBEventHandler SendMessageEventB;           public static void SendMessageBTest(string msg) {               SendMessageBEventHandler handle = SendMessageEventB;               if (handle != null) {                 handle("Obj", msg);             }         }     }

MainPage中使用

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void MainPage_Loaded(Object sender, RoutedEventArgs e) {             TestB.SendMessageEventB+=new TestB.SendMessageBEventHandler(TestB_SendMessageEventB);                   } //MainPage中接收  void TestB_SendMessageEventB(object sender, object obj) {             MessageBox.Show("B MainPageTestB  " + obj.ToString());         } //发送 private void button3_Click(object sender, RoutedEventArgs e)         {             TestB.SendMessageBTest(this.textBox3.Text);         }

Test中接收

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public Test(MainPage mainPage,TestA t) {             TestB.SendMessageEventB+=new TestB.SendMessageBEventHandler(TestB_SendMessageEventB);         }    void TestB_SendMessageEventB(object sender, object obj) {             MessageBox.Show("B TestB " + obj.ToString());         }

实验表示，使用静态的委托也能接收到多播消息

额，不懂如何上传源码Demo~~知道的告知下，嘿嘿 谢谢~