C# 4 and .NET 4

1364 ❘ ChaPTer 46 messAGe QueuinG
MyNewPublicQueue is created on the local host. To create a private queue, the pathname must include
Private$ ; for example, \Private$\MyNewPrivateQueue .
After the Create() method is invoked, properties of the queue can be changed. For example, using the
Label property, the label of the queue is set to Demo Queue . The sample program writes the path of
the queue and the format name to the console. The format name is automatically created with a UUID that
can be used to access the queue without the name of the server:
using System;
using System.Messaging;
namespace Wrox.ProCSharp.Messaging
{
class Program
{
static void Main()
{
using (var queue = MessageQueue.Create(@".\MyNewPublicQueue"))
{
queue.Label = "Demo Queue";
Console.WriteLine("Queue created:");
Console.WriteLine("Path: {0}", queue.Path);
Console.WriteLine("FormatName: {0}", queue.FormatName);
}
}
}
}
code snippet CreateMessageQueue/Program.cs
Administrative privileges are required to create a queue. Usually, you cannot expect the
user of your application to have administrative privileges. That’s why queues usually
are created with installation programs. Later in this chapter, you see how message
queues can be created with the MessageQueueInstaller class.
finding a queue
The pathname and the format name can be used to identify queues. To fi nd queues, you must differentiate
between public and private queues. Public queues are published in the Active Directory. For these queues, it
is not necessary to know the system where they are located. Private queues can be found only if the name of
the system where the queue is located is known.
You can fi nd public queues in the Active Directory domain by searching for the queue ’ s label, category,
or format name. You can also get all queues on a machine. The class MessageQueue has static
methods to search for queues: GetPublicQueuesByLabel() , GetPublicQueuesByCategory() , and
GetPublicQueuesByMachine() . The method GetPublicQueues() returns an array of all public queues in
the domain:
using System;
using System.Messaging;
namespace Wrox.ProCSharp.Messaging
{
class Program
{
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