MessageQueue.EndReceive Method (IAsyncResult)


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Completes the specified asynchronous receive operation.

Namespace:   System.Messaging
Assembly:  System.Messaging (in System.Messaging.dll)

public Message EndReceive(
	IAsyncResult asyncResult


Type: System.IAsyncResult

The IAsyncResult that identifies the asynchronous receive operation to finish and from which to retrieve an end result.

Return Value

Type: System.Messaging.Message

The Message associated with the completed asynchronous operation.

Exception Condition

The asyncResult parameter is null.


The syntax of the asyncResult parameter is not valid.


An error occurred when accessing a Message Queuing method.

When the ReceiveCompleted event is raised, EndReceive(IAsyncResult) completes the operation that was initiated by the BeginReceive call. To do so, EndReceive(IAsyncResult) receives the message.

BeginReceive can specify a time-out, which causes the ReceiveCompleted event to be raised if the time-out occurs before a message appears in the queue. When a time-out occurs without a message arriving in the queue, a subsequent call to EndReceive(IAsyncResult) throws an exception.

EndReceive(IAsyncResult) is used to read (removing from the queue) the message that caused the ReceiveCompleted event to be raised.

If you want to continue to asynchronously receive messages, you can again call BeginReceive after calling EndReceive(IAsyncResult).

The following table shows whether this method is available in various Workgroup modes.

Workgroup mode


Local computer


Local computer and direct format name


Remote computer


Remote computer and direct format name


The following code example chains asynchronous requests. It assumes there is a queue on the local computer called "myQueue". The Main function begins the asynchronous operation that is handled by the MyReceiveCompleted routine. MyReceiveCompleted processes the current message and begins a new asynchronous receive operation.

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[]

			// Add an event handler for the ReceiveCompleted event.
			myQueue.ReceiveCompleted += 
				new ReceiveCompletedEventHandler(MyReceiveCompleted);

			// Begin the asynchronous receive operation.


			// Do other work on the current thread.


		// 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);

				count += 1;
				if (count == 10)

				// Restart the asynchronous receive operation.
				// Handle sources of MessageQueueException.

			// Handle other exceptions.


.NET Framework
Available since 1.1
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