Export (0) Print
Expand All

MessageQueue.Receive Method (TimeSpan)

Receives the first message available in the queue referenced by the MessageQueue and waits until either a message is available in the queue, or the time-out expires.

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

public Message Receive(
	TimeSpan timeout
)

Parameters

timeout
Type: System.TimeSpan

A TimeSpan that indicates the time to wait until a new message is available for inspection.

Return Value

Type: System.Messaging.Message
A Message that references the first message available in the queue.

ExceptionCondition
ArgumentException

The value specified for the timeout parameter is not valid, possibly timeout is less than TimeSpan.Zero or greater than MessageQueue.InfiniteTimeout.

MessageQueueException

A message did not arrive in the queue before the time-out expired.

-or-

An error occurred when accessing a Message Queuing method

Use this overload to receive a message and return in a specified period of time if there are no messages in the queue.

The Receive method allows for the synchronous reading of a message, removing it from the queue. Subsequent calls to Receive will return the messages that follow in the queue, or new, higher priority messages.

To read the first message in a queue without removing it from the queue, use the Peek method. The Peek method always returns the first message in the queue, so subsequent calls to the method return the same message unless a higher priority message arrives in the queue.

Use a call to Receive when it is acceptable for the current thread to be blocked while it waits for a message to arrive in the queue. The thread will be blocked for the given period of time, or indefinitely if you specified the value InfiniteTimeout for the timeout parameter. If the application processing should continue without waiting for a message, consider using the asynchronous method, BeginReceive.

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

Workgroup mode

Available

Local computer

Yes

Local computer and direct format name

Yes

Remote computer

No

Remote computer and direct format name

Yes

The following code example receives a message from a queue and outputs information about that message to the screen. The example pauses execution for up to five seconds while waiting for a message to arrive in the queue.

using System;
using System.Messaging;

namespace MyProject
{
	// This class represents an object the following example  
	// receives from a queue. 

	public class Order
	{
		public int orderId;
		public DateTime orderTime;
	};	

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

		//************************************************** 
		// Provides an entry point into the application. 
		//		  
		// This example receives a message from a queue. 
		//************************************************** 

		public static void Main()
		{
			// Create a new instance of the class.
			MyNewQueue myNewQueue = new MyNewQueue();

			// Receive a message from a queue.
			myNewQueue.ReceiveMessage();

			return;
		}


		//************************************************** 
		// Receives a message containing an Order. 
		//************************************************** 

		public void ReceiveMessage()
		{
			// Connect to the a queue on the local computer.
			MessageQueue myQueue = new MessageQueue(".\\myQueue");

			// Set the formatter to indicate body contains an Order.
			myQueue.Formatter = new XmlMessageFormatter(new Type[]
				{typeof(MyProject.Order)});
			
			try
			{
				// Receive and format the message.  
				// Wait 5 seconds for a message to arrive.
				Message myMessage =	myQueue.Receive(new 
					TimeSpan(0,0,5)); 
				Order myOrder = (Order)myMessage.Body;

				// Display message information.
				Console.WriteLine("Order ID: " + 
					myOrder.orderId.ToString());
				Console.WriteLine("Sent: " + 
					myOrder.orderTime.ToString());
			}

			catch (MessageQueueException e)
			{
				// Handle no message arriving in the queue. 
				if (e.MessageQueueErrorCode == 
					MessageQueueErrorCode.IOTimeout)
				{
					Console.WriteLine("No message arrived in queue.");
				}			

				// Handle other sources of a MessageQueueException.
			}
			
			// Handle invalid serialization format. 
			catch (InvalidOperationException e)
			{
				Console.WriteLine(e.Message);
			}
			
			// Catch other exceptions as necessary. 

			return;
		}
	}
}

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Show:
© 2014 Microsoft