C# 4 and .NET 4

Programming Message Queuing ❘ 1363
message queue Properties
After a queue is created, you can modify the
queue ’ s properties with the Computer Management
snap - in by selecting the queue in the tree pane
and selecting the Action Properties menu (see
Figure 46 - 6).
Several options can be confi gured:
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The label is the name of the queue that can be used
to search for the queue.
The type ID, which is by default, set to
{00000000– 0000 – 0000 – 0000 – 000000000000}
to map multiple queues to a single category or type.
Report queues use a specifi c type ID, as discussed
earlier. A type ID is a universal unique ID (UUID)
or GUID.
figure 46-6
Custom type identifi ers can be created with the uuidgen.exe or guidgen.exe utilities.
uuidgen.exe is a command-line utility used to create unique IDs, and guidgen.exe is
a graphical version to create UUIDs.
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The maximum size of all messages of a queue can be limited to avoid fi lling up the disk.
When checked, the Authenticated option allows only authenticated users to write and read messages
to and from the queue.
With the Privacy Level option, the content of the message can be encrypted. The possible values to
set are None, Optional, or Body. None means that no encrypted messages are accepted, Body accepts
only encrypted messages, and the default Optional value accepts both.
Target journaling can be confi gured with the Journal settings. With this option, copies of the
messages received are stored in the journal. The maximum size of disk space that is occupied can be
confi gured for the journal messages of a queue. When the maximum size is reached, target journaling
is ceased.
With the confi guration option Multicast, you can defi ne a multicast IP address for the queue. The
same multicast IP address can be used with different nodes in the network, so that a message sent to a
single address is received with multiple queues.
Programming message queuing
Now that you understand the architecture of Message Queuing, you can look into the programming. In the
next sections, you see how to create and control queues, and how to send and receive messages.
You also build a small course order application that consists of a sending and a receiving part.
Creating a message queue
You ’ ve already seen how to create message queues with the Computer Management utility. Message queues
can be created programmatically with the Create() method of the MessageQueue class.
With the Create() method, the path of the new queue must be passed. The path consists of the host
name where the queue is located and the name of the queue. In the following example, the queue
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