MessageQueue.GetPublicQueues Method

Definition

Namespace:

System.Messaging

Assembly:

System.Messaging.dll

Retrieves all the public queues on the network.

Overloads

GetPublicQueues()	Retrieves all the public queues on the network.
GetPublicQueues(MessageQueueCriteria)	Retrieves all the public queues on the network that meet the specified criteria.

GetPublicQueues()

Retrieves all the public queues on the network.

C#

public static System.Messaging.MessageQueue[] GetPublicQueues();

Returns

MessageQueue[]

An array of MessageQueue objects that reference the retrieved public queues.

Exceptions

MessageQueueException

An error occurred when accessing a Message Queuing method.

Examples

The following code example retrieves lists of queues.

C#

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 gets lists of queues by a variety
        // of criteria.
        //**************************************************

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

            // Send normal and high priority messages.
            myNewQueue.GetQueuesByCategory();
            myNewQueue.GetQueuesByLabel();
            myNewQueue.GetQueuesByComputer();
            myNewQueue.GetAllPublicQueues();
            myNewQueue.GetPublicQueuesByCriteria();
            myNewQueue.GetPrivateQueues();
                        
            return;
        }

        //**************************************************
        // Gets a list of queues with a specified category.
        // Sends a broadcast message to all queues in that
        // category.
        //**************************************************
        
        public void GetQueuesByCategory()
        {
            // Get a list of queues with the specified category.
            MessageQueue[] QueueList =
                MessageQueue.GetPublicQueuesByCategory(new
                Guid("{00000000-0000-0000-0000-000000000001}"));

            // Send a broadcast message to each queue in the array.
            foreach(MessageQueue queueItem in QueueList)
            {
                queueItem.Send("Broadcast message.");
            }
            
            return;
        }

        //**************************************************
        // Gets a list of queues with a specified label.
        // Sends a broadcast message to all queues with that
        // label.
        //**************************************************
        
        public void GetQueuesByLabel()
        {
            // Get a list of queues with the specified label.
            MessageQueue[] QueueList =
                MessageQueue.GetPublicQueuesByLabel("My Label");

            // Send a broadcast message to each queue in the array.
            foreach(MessageQueue queueItem in QueueList)
            {
                queueItem.Send("Broadcast message.");
            }
            
            return;
        }

        //**************************************************
        // Gets a list of queues on a specified computer.
        // Displays the list on screen.
        //**************************************************
        
        public void GetQueuesByComputer()
        {
            // Get a list of queues on the specified computer.
            MessageQueue[] QueueList =
                MessageQueue.GetPublicQueuesByMachine("MyComputer");

            // Display the paths of the queues in the list.
            foreach(MessageQueue queueItem in QueueList)
            {
                Console.WriteLine(queueItem.Path);
            }

            return;
        }

        //**************************************************
        // Gets a list of all public queues.
        //**************************************************
        
        public void GetAllPublicQueues()
        {
            // Get a list of public queues.
            MessageQueue[] QueueList =
                MessageQueue.GetPublicQueues();
    
            return;
        }

        //**************************************************
        // Gets a list of all public queues that match
        // specified criteria. Displays the list on
        // screen.
        //**************************************************
        
        public void GetPublicQueuesByCriteria()
        {
            // Define criteria to filter the queues.
            MessageQueueCriteria myCriteria = new
                MessageQueueCriteria();
            myCriteria.CreatedAfter = DateTime.Now.Subtract(new
                TimeSpan(1,0,0,0));
            myCriteria.ModifiedBefore = DateTime.Now;
            myCriteria.MachineName = ".";
            myCriteria.Label = "My Queue";
            
            // Get a list of queues with that criteria.
            MessageQueue[] QueueList =
                MessageQueue.GetPublicQueues(myCriteria);

            // Display the paths of the queues in the list.
            foreach(MessageQueue queueItem in QueueList)
            {
                Console.WriteLine(queueItem.Path);
            }

            return;
        }

        //**************************************************
        // Gets a list of private queues on the local
        // computer. Displays the list on screen.
        //**************************************************
        
        public void GetPrivateQueues()
        {
            // Get a list of queues with the specified category.
            MessageQueue[] QueueList =
                MessageQueue.GetPrivateQueuesByMachine(".");

            // Display the paths of the queues in the list.
            foreach(MessageQueue queueItem in QueueList)
            {
                Console.WriteLine(queueItem.Path);
            }
            
            return;
        }
    }
}

Remarks

Use this overload if you want a complete list of all the public queues on the network. If you want to restrict the list by certain criteria, such as MachineName, Category, or last modified time use another overload of this method. (Alternatively, you can use GetPublicQueuesByMachine(String), GetPublicQueuesByCategory(Guid), or GetPublicQueuesByLabel(String).)

GetPublicQueues retrieves a static snapshot of the queues. To interact with a dynamic list of the queues, use GetMessageQueueEnumerator.

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

Workgroup mode	Available
Local computer	No
Local computer and direct format name	No
Remote computer	No
Remote computer and direct format name	No

See also

• GetMessageQueueEnumerator()

GetPublicQueues(MessageQueueCriteria)

Retrieves all the public queues on the network that meet the specified criteria.

C#

public static System.Messaging.MessageQueue[] GetPublicQueues(System.Messaging.MessageQueueCriteria criteria);

Parameters

criteria

MessageQueueCriteria

A MessageQueueCriteria that contains the criteria used to filter the queues.

Returns

MessageQueue[]

An array of MessageQueue objects that reference the retrieved public queues.

Exceptions

MessageQueueException

An error occurred when accessing a Message Queuing method.

Examples

The following code example retrieves lists of queues.

C#

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 gets lists of queues by a variety
        // of criteria.
        //**************************************************

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

            // Send normal and high priority messages.
            myNewQueue.GetQueuesByCategory();
            myNewQueue.GetQueuesByLabel();
            myNewQueue.GetQueuesByComputer();
            myNewQueue.GetAllPublicQueues();
            myNewQueue.GetPublicQueuesByCriteria();
            myNewQueue.GetPrivateQueues();
                        
            return;
        }

        //**************************************************
        // Gets a list of queues with a specified category.
        // Sends a broadcast message to all queues in that
        // category.
        //**************************************************
        
        public void GetQueuesByCategory()
        {
            // Get a list of queues with the specified category.
            MessageQueue[] QueueList =
                MessageQueue.GetPublicQueuesByCategory(new
                Guid("{00000000-0000-0000-0000-000000000001}"));

            // Send a broadcast message to each queue in the array.
            foreach(MessageQueue queueItem in QueueList)
            {
                queueItem.Send("Broadcast message.");
            }
            
            return;
        }

        //**************************************************
        // Gets a list of queues with a specified label.
        // Sends a broadcast message to all queues with that
        // label.
        //**************************************************
        
        public void GetQueuesByLabel()
        {
            // Get a list of queues with the specified label.
            MessageQueue[] QueueList =
                MessageQueue.GetPublicQueuesByLabel("My Label");

            // Send a broadcast message to each queue in the array.
            foreach(MessageQueue queueItem in QueueList)
            {
                queueItem.Send("Broadcast message.");
            }
            
            return;
        }

        //**************************************************
        // Gets a list of queues on a specified computer.
        // Displays the list on screen.
        //**************************************************
        
        public void GetQueuesByComputer()
        {
            // Get a list of queues on the specified computer.
            MessageQueue[] QueueList =
                MessageQueue.GetPublicQueuesByMachine("MyComputer");

            // Display the paths of the queues in the list.
            foreach(MessageQueue queueItem in QueueList)
            {
                Console.WriteLine(queueItem.Path);
            }

            return;
        }

        //**************************************************
        // Gets a list of all public queues.
        //**************************************************
        
        public void GetAllPublicQueues()
        {
            // Get a list of public queues.
            MessageQueue[] QueueList =
                MessageQueue.GetPublicQueues();
    
            return;
        }

        //**************************************************
        // Gets a list of all public queues that match
        // specified criteria. Displays the list on
        // screen.
        //**************************************************
        
        public void GetPublicQueuesByCriteria()
        {
            // Define criteria to filter the queues.
            MessageQueueCriteria myCriteria = new
                MessageQueueCriteria();
            myCriteria.CreatedAfter = DateTime.Now.Subtract(new
                TimeSpan(1,0,0,0));
            myCriteria.ModifiedBefore = DateTime.Now;
            myCriteria.MachineName = ".";
            myCriteria.Label = "My Queue";
            
            // Get a list of queues with that criteria.
            MessageQueue[] QueueList =
                MessageQueue.GetPublicQueues(myCriteria);

            // Display the paths of the queues in the list.
            foreach(MessageQueue queueItem in QueueList)
            {
                Console.WriteLine(queueItem.Path);
            }

            return;
        }

        //**************************************************
        // Gets a list of private queues on the local
        // computer. Displays the list on screen.
        //**************************************************
        
        public void GetPrivateQueues()
        {
            // Get a list of queues with the specified category.
            MessageQueue[] QueueList =
                MessageQueue.GetPrivateQueuesByMachine(".");

            // Display the paths of the queues in the list.
            foreach(MessageQueue queueItem in QueueList)
            {
                Console.WriteLine(queueItem.Path);
            }
            
            return;
        }
    }
}

Remarks

If you want to filter all the public queues on the network by label, category, or computer name, the MessageQueue class contains specific methods that provide that functionality (GetPublicQueuesByLabel(String), GetPublicQueuesByCategory(Guid), and GetPublicQueuesByMachine(String), respectively). Use this overload to get a list of all the public queues on the network that meet more than one of these criteria (for example, if you want to specify both a label and a category). You can also filter by message criteria other than Label, Category, and MachineName. For example, you use this overload to filter by a queue's last-modified time. Simply create a new instance of the MessageQueueCriteria class, set the appropriate properties in the instance, and pass the instance as the criteria parameter.

GetPublicQueues retrieves a static snapshot of the queues. To interact with a dynamic list of the queues, use GetMessageQueueEnumerator.

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

Workgroup mode	Available
Local computer	No
Local computer and direct format name	No
Remote computer	No
Remote computer and direct format name	No

See also

• MessageQueueCriteria
• GetMessageQueueEnumerator()