How To Filter Messages with Specific Property Values? (176016)
The information in this article applies to:
- Microsoft Message Queue Server (MSMQ) 1.0
This article was previously published under Q176016 SUMMARY
When you retrieve a message that is not at the front of the queue and its
properties match with specific values (values for PROPID_M_MSGID,
PROPID_M_CORRELATIONID, or any other property), use MQCreateCursor(),
MQ_ACTION_PEEK_NEXT, and MQ_ACTION_PEEK_CURRENT functionality in
MQReceiveMessage().
MORE INFORMATION
When you use Microsoft Message Queue Server 1.0, applications need to
perform filtering on their own. Examine the appropriate message properties
and decide whether to skip to the next message or not. Note that you
usually do not need to rescan the entire queue. By using a cursor, you
examine only new messages arriving to the queue. The MQ_ACTION_PEEK_NEXT
and MQ_ACTION_PEEK_CURRENT functionality in C API MQReceiveMessage() may be
used to implement your own filtering logic.
The receive/peek function is designed to always start at the beginning of
the queue and then allow a cursor to be used to traverse the messages in
the queue. You are unable to directly address a specific message by any of
its properties. One way to get to the specific message is to specify a
cursor and then PEEK_NEXT your way through the messages, retrieving only
the specific property as your search criteria (PROPID_M_MSGID or any other
property). When you find the message you want, you can perform a full
receive/peek CURRENT operation to retrieve other properties of that
message.
Retrieving arbitrary properties for a message works for the MSMQ C API
only. ActiveX Receive methods let you exclude body and DestinationQueueInfo
by specifying WantBody and WantDestinationQueue flags.
REFERENCES
For more information or to see a code example to find a specific message
using cursors, search the "Reading Messages Using a Cursor" topic in the
MSMQ SDK help file.
(c) Microsoft Corporation 1997, All Rights Reserved. Contributions by Syed
Yousuf, Microsoft Corporation
| Modification Type: | Minor | Last Reviewed: | 6/30/2004 |
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| Keywords: | kbhowto KB176016 |
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