MessageQueue.ReceiveCompleted Evento

  • Referencia

Definición

Espacio de nombres:
System.Messaging
Ensamblado:
System.Messaging.dll

Se produce cuando se quita un mensaje de la cola. La operación asincrónica BeginReceive() provoca este evento.

public:
 event System::Messaging::ReceiveCompletedEventHandler ^ ReceiveCompleted;
[System.Messaging.MessagingDescription("MQ_ReceiveCompleted")]
public event System.Messaging.ReceiveCompletedEventHandler ReceiveCompleted;
[<System.Messaging.MessagingDescription("MQ_ReceiveCompleted")>]
member this.ReceiveCompleted : System.Messaging.ReceiveCompletedEventHandler 
Public Custom Event ReceiveCompleted As ReceiveCompletedEventHandler

Tipo de evento

ReceiveCompletedEventHandler
Atributos
MessagingDescriptionAttribute

Ejemplos

En el ejemplo de código siguiente se crea un controlador de eventos denominado MyReceiveCompleted, se adjunta al delegado del ReceiveCompleted controlador de eventos y se llama BeginReceive a para iniciar una operación de recepción asincrónica en la cola que se encuentra en la ruta de acceso ".\myQueue". Cuando se genera un ReceiveCompleted evento, el ejemplo recibe el mensaje y escribe su cuerpo en la pantalla. A continuación, el ejemplo llama BeginReceive de nuevo para iniciar una nueva operación de recepción asincrónica.

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

using namespace System;
using namespace System::Messaging;
ref class MyNewQueue
{
public:

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

      // End the asynchronous Receive operation.
      Message^ m = mq->EndReceive( asyncResult->AsyncResult );

      // Display message information on the screen.
      Console::WriteLine( "Message: {0}", m->Body );

      // Restart the asynchronous Receive operation.
      mq->BeginReceive();
      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();

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

using System;
using System.Messaging;

namespace MyProject
{
    /// <summary>
    /// Provides a container class for the example.
    /// </summary>
    public class MyNewQueue
    {

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

            return;
        }

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

            // End the asynchronous Receive operation.
            Message m = mq.EndReceive(asyncResult.AsyncResult);

            // Display message information on the screen.
            Console.WriteLine("Message: " + (string)m.Body);

            // Restart the asynchronous Receive operation.
            mq.BeginReceive();
            
            return;
        }
    }
}

Imports System.Messaging

Public Class MyNewQueue


        '
        ' 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()

            ' 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)

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

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

            ' Display message information on the screen.
            Console.WriteLine(("Message: " + CStr(m.Body)))

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

            Return

        End Sub

End Class

Comentarios

BeginReceive se usa en el procesamiento asincrónico para generar el ReceiveCompleted evento cuando un mensaje está disponible en la cola.

EndReceive(IAsyncResult) se usa para completar la operación iniciada por una llamada a BeginReceive y ver el mensaje cuando se genera el ReceiveCompleted evento.

Cuando se crea un delegado ReceiveCompletedEventHandler, se identifica el método que controlará el evento. Para asociar el evento al controlador, se debe agregar una instancia del delegado al evento. Siempre que se produce el evento, se llama a su controlador, a menos que se quite el delegado. Para obtener más información sobre los delegados del controlador de eventos, vea Control y generación de eventos.

Se aplica a

Consulte también