MessageQueueEnumerator Class

Provides a forward-only cursor to enumerate through messages in a message queue.

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

public class MessageQueueEnumerator : MarshalByRefObject, 
	IEnumerator, IDisposable

Use MessageQueueEnumerator for dynamic interaction with queues on the network. Methods available through the MessageQueue class can return either a MessageQueueEnumerator containing a dynamic list of queues, or an array that contains a snapshot of the queue collection at the time the specified method was called.

There is no defined ordering of queues in a network. They are not ordered, for example, by computer, label, public or private status, or other user-accessible criteria. A MessageQueueEnumerator is a cursor, initialized to the head of a dynamic list. You can move the cursor to the first queue of the enumeration by calling MoveNext. After the enumerator has been initialized, you can use MoveNext to step forward through the remaining queues.

It is not possible to step backward with a MessageQueueEnumerator. A cursor only allows forward movement through the queue enumeration. However, you can call Reset to reset the enumeration and put the cursor at the beginning of the list again. Because the enumerator is dynamic, a queue that is appended beyond the cursor's current position can be accessed by the enumerator. A queue that is inserted before the cursor's current position cannot be accessed without first calling Reset.

The following code example iterates through all the message queues in the network, and examines the path for each queue. Finally, it displays the number of public queues on the network.

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 uses a cursor to step through the 
		// message queues and list the public queues on the 
		// network. 
		//************************************************** 

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

			// Output the count of Lowest priority messages.
			myNewQueue.ListPublicQueues();
						
			return;
		}


		//************************************************** 
		// Iterates through message queues and examines the 
		// path for each queue. Also displays the number of 
		// public queues on the network. 
		//************************************************** 
		
		public void ListPublicQueues()
		{
			// Holds the count of private queues.
			uint numberQueues = 0;
	
			// Get a cursor into the queues on the network.
			MessageQueueEnumerator myQueueEnumerator = 
				MessageQueue.GetMessageQueueEnumerator();

			// Move to the next queue and read its path. 
			while(myQueueEnumerator.MoveNext())
			{
				// Increase the count if priority is Lowest.
				Console.WriteLine(myQueueEnumerator.Current.Path);
				numberQueues++;
			}

			// Display final count.
			Console.WriteLine("Number of public queues: " + 
				numberQueues.ToString());
			
			return;
		}
	}
}
#using <mscorlib.dll>
#using <System.dll>
#using <System.Messaging.dll>
using namespace System;
using namespace System::Messaging;

//**************************************************
// Iterates through message queues and examines the
// path for each queue. Also displays the number of
// public queues on the network.
//**************************************************

void ListPublicQueues()
{
    // Holds the count of private queues.
    int numberQueues = 0;

    // Get a cursor into the queues on the network.
    MessageQueueEnumerator* myQueueEnumerator = 
        MessageQueue::GetMessageQueueEnumerator();

    // Move to the next queue and read its path.
    while(myQueueEnumerator->MoveNext())
    {
        // Increase the count if priority is Lowest.
        Console::WriteLine(myQueueEnumerator->Current->Path);
        numberQueues++;
    }

    // Display final count.
    Console::WriteLine(S"Number of public queues: {0}", __box(numberQueues));

    return;
}

//**************************************************
// Provides an entry point into the application.
//		 
// This example uses a cursor to step through the
// message queues and list the public queues on the
// network.
//**************************************************

int main()
{
    // Output the count of Lowest priority messages.
    ListPublicQueues();
}

System.Object
  System.MarshalByRefObject
    System.Messaging.MessageQueueEnumerator

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

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

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
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