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微软docs上的例子，可以参考学习：

C#using System;using System.IO;using System.Reflection;using System.Windows.Forms;public class Example{
      public static void Main()   {
         Action
   
     outputMessage = null;      outputMessage += Console.WriteLine;      outputMessage += OutputToFile;      outputMessage += ShowMessageBox;//       Dim output1 As Action(Of String) = AddressOf Console.WriteLine//       Dim output2 As Action(Of String) = AddressOf OutputToFile//       Dim output3 As Action(Of String) = AddressOf MessageBox.Show////       outputMessage = [Delegate].Combine( { output1, output2, output3 } )      Console.WriteLine("Invocation list has {0} methods.",                        outputMessage.GetInvocationList().Length);      // Invoke delegates normally.      outputMessage("Hello there!");      Console.WriteLine("Press 
    
      to continue...");      Console.ReadLine();      // Invoke each delegate in the invocation list in reverse order.      for (int ctr = outputMessage.GetInvocationList().Length - 1; ctr >= 0; ctr--) {
            var outputMsg = outputMessage.GetInvocationList()[ctr];         outputMsg.DynamicInvoke("Greetings and salutations!");      }      Console.WriteLine("Press 
     
       to continue...");      Console.ReadLine();      // Invoke each delegate that doesn't write to a file.      for (int ctr = 0; ctr < outputMessage.GetInvocationList().Length; ctr++) {
            var outputMsg = outputMessage.GetInvocationList()[ctr];         if (! outputMsg.GetMethodInfo().Name.Contains("File"))            outputMsg.DynamicInvoke( new String[] {
    "Hi!" } );      }   }   private static void OutputToFile(String s)   {
         var sw = new StreamWriter(@".\output.txt");      sw.WriteLine(s);      sw.Close();   }   private static void ShowMessageBox(String s)   {
         MessageBox.Show(s);   }}
     
    
   

ＶＢ：Imports System.IOImports System.ReflectionImports System.Windows.FormsModule Example   Public outputMessage As Action(Of String)      Public Sub Main()      Dim output1 As Action(Of String) = AddressOf Console.WriteLine      Dim output2 As Action(Of String) = AddressOf OutputToFile       Dim output3 As Action(Of String) = AddressOf MessageBox.Show            outputMessage = [Delegate].Combine( { output1, output2, output3 } )      Console.WriteLine("Invocation list has {
  0} methods.",                         outputMessage.GetInvocationList().Count)      ' Invoke delegates normally.      outputMessage("Hello there!")      Console.WriteLine("Press 
   
     to continue...")      Console.ReadLine()            ' Invoke each delegate in the invocation list in reverse order.      For ctr As Integer = outputMessage.GetInvocationList().Count - 1 To 0 Step -1          Dim outputMsg = outputMessage.GetInvocationList(ctr)          outputMsg.DynamicInvoke("Greetings and salutations!")      Next      Console.WriteLine("Press 
    
      to continue...")      Console.ReadLine()            ' Invoke each delegate that doesn't write to a file.      For ctr As Integer = 0 To outputMessage.GetInvocationList().Count - 1          Dim outputMsg = outputMessage.GetInvocationList(ctr)         If Not outputMsg.GetMethodInfo().Name.Contains("File") Then            outputMsg.DynamicInvoke( { "Hi!" } )         End If      Next   End Sub      Private Sub OutputToFile(s As String)      Dim sw As New StreamWriter(".\output.txt")      sw.WriteLine(s)      sw.Close()   End SubEnd Module另外一个例子，委托事件返回的类型是Task： Public Sub Main()   Dim action As Func(Of String, Task) = AddressOf upload   Dim action1 As Func(Of String, Task) = AddressOf upload1   Dim delegateComb = [Delegate].Combine({action, action1})   Await delegateComb.DynamicInvoke(autoCommand)  End Sub    Private Async Function upload1(ByVal msg As String) As Task        Await Task.Delay(3000)    End Function    Private Async Function upload2(ByVal msg As String) As Task        Await Task.Delay(3000)    End Function
    
   

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