MessageQueue.EndReceive(IAsyncResult) Methode

public:
 System::Messaging::Message ^ EndReceive(IAsyncResult ^ asyncResult);

public System.Messaging.Message EndReceive(IAsyncResult asyncResult);

member this.EndReceive : IAsyncResult -> System.Messaging.Message

Public Function EndReceive (asyncResult As IAsyncResult) As Message

Parameters

Retouren

De Message gekoppelde aan de voltooide asynchrone bewerking.

Uitzonderingen

Voorbeelden

In het volgende codevoorbeeld worden asynchrone aanvragen gekoppeld. Hierbij wordt ervan uitgegaan dat er een wachtrij is op de lokale computer met de naam 'myQueue'. De Main functie begint de asynchrone bewerking die wordt verwerkt door de MyReceiveCompleted routine. MyReceiveCompleted verwerkt het huidige bericht en begint een nieuwe asynchrone ontvangstbewerking.

#using <system.dll>
#using <system.messaging.dll>

using namespace System;
using namespace System::Messaging;
using namespace System::Threading;

ref class MyNewQueue
{
public:

   // Define static class members.
   static ManualResetEvent^ signal = gcnew ManualResetEvent( false );
   static int count = 0;

   // Provides an event handler for the ReceiveCompleted
   // event.
   static void MyReceiveCompleted( Object^ source, ReceiveCompletedEventArgs^ asyncResult )
   {
      try
      {
         // Connect to the queue.
         MessageQueue^ mq = dynamic_cast<MessageQueue^>(source);

         // End the asynchronous receive operation.
         mq->EndReceive( asyncResult->AsyncResult );
         count += 1;
         if ( count == 10 )
         {
            signal->Set();
         }

         // Restart the asynchronous receive operation.
         mq->BeginReceive();
      }
      catch ( MessageQueueException^ ) 
      {
         // Handle sources of MessageQueueException.
      }

      // Handle other exceptions.
      return;
   }
};

// Provides an entry point into the application.
//         
// This example performs asynchronous receive
// operation processing.
int main()
{
   // Create an instance of MessageQueue. Set its formatter.
   MessageQueue^ myQueue = gcnew MessageQueue( ".\\myQueue" );
   array<Type^>^p = gcnew array<Type^>(1);
   p[ 0 ] = String::typeid;
   myQueue->Formatter = gcnew XmlMessageFormatter( p );

   // Add an event handler for the ReceiveCompleted event.
   myQueue->ReceiveCompleted += gcnew ReceiveCompletedEventHandler( MyNewQueue::MyReceiveCompleted );

   // Begin the asynchronous receive operation.
   myQueue->BeginReceive();
   MyNewQueue::signal->WaitOne();

   // Do other work on the current thread.
   return 0;
}

using System;
using System.Messaging;
using System.Threading;

namespace MyProject
{
    /// <summary>
    /// Provides a container class for the example.
    /// </summary>
    public class MyNewQueue
    {
        // Define static class members.
        static ManualResetEvent signal = new ManualResetEvent(false);
        static int count = 0;

        //**************************************************
        // Provides an entry point into the application.
        //		
        // This example performs asynchronous receive
        // operation processing.
        //**************************************************

        public static void Main()
        {
            // Create an instance of MessageQueue. Set its formatter.
            MessageQueue myQueue = new MessageQueue(".\\myQueue");
            myQueue.Formatter = new XmlMessageFormatter(new Type[]
                {typeof(String)});

            // Add an event handler for the ReceiveCompleted event.
            myQueue.ReceiveCompleted +=
                new ReceiveCompletedEventHandler(MyReceiveCompleted);
            
            // Begin the asynchronous receive operation.
            myQueue.BeginReceive();

            signal.WaitOne();
            
            // Do other work on the current thread.

            return;
        }

        //***************************************************
        // Provides an event handler for the ReceiveCompleted
        // event.
        //***************************************************
        
        private static void MyReceiveCompleted(Object source,
            ReceiveCompletedEventArgs asyncResult)
        {
            try
            {
                // Connect to the queue.
                MessageQueue mq = (MessageQueue)source;

                // End the asynchronous receive operation.
                Message m = mq.EndReceive(asyncResult.AsyncResult);
                
                count += 1;
                if (count == 10)
                {
                    signal.Set();
                }

                // Restart the asynchronous receive operation.
                mq.BeginReceive();
            }
            catch(MessageQueueException)
            {
                // Handle sources of MessageQueueException.
            }
            
            // Handle other exceptions.
            
            return;
        }
    }
}

Imports System.Messaging
Imports System.Threading




' Provides a container class for the example.

Public Class MyNewQueue

        ' Define static class members.
        Private Shared signal As New ManualResetEvent(False)
        Private Shared count As Integer = 0



        ' Provides an entry point into the application.
        '		 
        ' This example performs asynchronous receive
        ' operation processing.


        Public Shared Sub Main()
            ' Create an instance of MessageQueue. Set its formatter.
            Dim myQueue As New MessageQueue(".\myQueue")
            myQueue.Formatter = New XmlMessageFormatter(New Type() _
                {GetType([String])})

            ' Add an event handler for the ReceiveCompleted event.
            AddHandler myQueue.ReceiveCompleted, AddressOf _
                MyReceiveCompleted

            ' Begin the asynchronous receive operation.
            myQueue.BeginReceive()

            signal.WaitOne()

            ' Do other work on the current thread.

            Return

        End Sub



        ' Provides an event handler for the ReceiveCompleted
        ' event.


        Private Shared Sub MyReceiveCompleted(ByVal [source] As _
            [Object], ByVal asyncResult As ReceiveCompletedEventArgs)

            Try
                ' Connect to the queue.
                Dim mq As MessageQueue = CType([source], MessageQueue)

                ' End the asynchronous receive operation.
                Dim m As Message = _
                    mq.EndReceive(asyncResult.AsyncResult)

                count += 1
                If count = 10 Then
                    signal.Set()
                End If

                ' Restart the asynchronous receive operation.
                mq.BeginReceive()

            Catch
                ' Handle sources of MessageQueueException.

                ' Handle other exceptions.

            End Try

            Return

        End Sub

End Class

Opmerkingen

Wanneer de ReceiveCompleted gebeurtenis wordt gegenereerd, EndReceive(IAsyncResult) voltooit u de bewerking die is gestart door de BeginReceive aanroep. Dit doet u EndReceive(IAsyncResult) door het bericht te ontvangen.

BeginReceive kan een time-out opgeven, waardoor de ReceiveCompleted gebeurtenis wordt gegenereerd als er een time-out optreedt voordat een bericht in de wachtrij wordt weergegeven. Wanneer er een time-out optreedt zonder dat er een bericht in de wachtrij binnenkomt, genereert een volgende aanroep om een uitzondering te EndReceive(IAsyncResult) genereren.

EndReceive(IAsyncResult) wordt gebruikt om het bericht te lezen (verwijderen uit de wachtrij) waardoor de ReceiveCompleted gebeurtenis is gegenereerd.

Als u asynchroon berichten wilt blijven ontvangen, kunt u opnieuw bellen BeginReceive na het bellen EndReceive(IAsyncResult).

In de volgende tabel ziet u of deze methode beschikbaar is in verschillende werkgroepmodi.

Zie ook

• BeginReceive()
• ReceiveCompleted