Delegate.GetInvocationList Método

Definición

Espacio de nombres:

System

Ensamblado:

System.Runtime.dll

Ensamblado:

mscorlib.dll

Ensamblado:

netstandard.dll

Devuelve la lista de invocaciones del delegado.

public:
 virtual cli::array <Delegate ^> ^ GetInvocationList();

public virtual Delegate[] GetInvocationList ();

abstract member GetInvocationList : unit -> Delegate[]
override this.GetInvocationList : unit -> Delegate[]

Public Overridable Function GetInvocationList () As Delegate()

Devoluciones

Delegate[]

Matriz de delegados que representa la lista de invocaciones del delegado actual.

Ejemplos

En el ejemplo siguiente se asignan tres métodos a un delegado. A continuación, llama al GetInvocationList método para obtener un recuento total de los métodos asignados al delegado, para ejecutar los delegados en orden inverso y para ejecutar los métodos cuyo nombre no incluya la subcadena "File".

using System;
using System.IO;
using System.Reflection;
using System.Windows.Forms;

public class Example
{
   public static void Main()
   {
      Action<String> 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 <Enter> 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 <Enter> 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);
   }
}

open System
open System.IO
open System.Reflection
open System.Windows.Forms

let outputToFile (s: string) =
    use sw = new StreamWriter(@".\output.txt")
    sw.WriteLine s

let showMessageBox s =
    MessageBox.Show s |> ignore

let outputMessage =
    Delegate.Combine(
        Action<string>(Console.WriteLine),
        Action<string>(outputToFile),
        Action<string>(showMessageBox))
    :?> Action<string>

printfn $"Invocation list has {outputMessage.GetInvocationList().Length} methods."

// Invoke delegates normally.
outputMessage.Invoke "Hello there!"
printfn "Press <Enter> to continue..."
stdin.ReadLine() |> ignore

// Invoke each delegate in the invocation list in reverse order.
for i = outputMessage.GetInvocationList().Length - 1 downto 0 do
    let outputMsg = outputMessage.GetInvocationList()[i]
    outputMsg.DynamicInvoke "Greetings and salutations!"
    |> ignore

printfn "Press <Enter> to continue..."
stdin.ReadLine() |> ignore

// Invoke each delegate that doesn't write to a file.
for i = 0 to outputMessage.GetInvocationList().Length - 1 do
    let outputMsg = outputMessage.GetInvocationList()[i]
    if not (outputMsg.GetMethodInfo().Name.Contains "File") then
        outputMsg.DynamicInvoke "Hi!"
        |> ignore

Imports System.IO
Imports System.Reflection
Imports System.Windows.Forms

Module 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 <Enter> 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 <Enter> 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 Sub
End Module

Comentarios

Cada delegado de la matriz representa exactamente un método.

El orden de los delegados de la matriz es el mismo orden en el que el delegado actual invoca los métodos que representan esos delegados.