Windows service receiving MSMQ message only first time when service starts

Question

0.00/5 (No votes)

See more:

I am first time working with both windows service and MSMQ. I am trying to read messages from queue. When I start my windows service, i am receiving only first message and next message not able to read, service is still running. if I restart the service It is reading first message from the queue. Please let me know how to fix this issue.

What I have tried:

MessageQueue msMq = null;

protected override void OnStart(string[] args)
    {
        
        JobModel j = new JobModel();
        msMq = new MessageQueue(queueRequestName);
        msMq.ReceiveCompleted += MsMq_ReceiveCompleted1;
        try
        {            
            if (msMq != null)
            {                    
                msMq.Formatter = new XmlMessageFormatter(new Type[] { typeof(JobModel) });
                var message = (JobModel)msMq.BeginReceive();        

            }
        }      
        catch (Exception eee)
        {
            Console.Write(eee.ToString());
        }
        
    }
   private void MsMq_ReceiveCompleted(object sender, ReceiveCompletedEventArgs e)
        {
            var msMq = (MessageQueue)sender;
            var msg = msMq.EndReceive(e.AsyncResult); 
            //ToDo: process message          
            msMq.BeginReceive();
        }

Posted 19-Mar-18 8:28am

Member 11837253

Updated 28-Mar-18 22:05pm

v3

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Christiaan van Bergen · Accepted Answer · 2018-03-28T22:06:00

Solution 1

Use something that keeps on listening. The Receive method on a MessageQueue will do that.

For example:

C#

var mq = new System.Messaging.MessageQueue(@".\Private$\SomeQueue");
while (mq.CanRead) // or any other loop condition
{
    var msg = mq.Receive();
    //do something with your message here
}

The Receive method will block untill a message is received at which point it'll remove the message from the queue and return it.

HTH Christiaan

Posted 28-Mar-18 22:06pm

Christiaan van Bergen

Comments

Christiaan van Bergen 4-Apr-18 15:53pm

Have a while-loop around it, otherwise it will still not continue listening after the message has been processed.

Member 11837253 4-Apr-18 16:25pm

I added but no luck. I modified code
public partial class Service1 : ServiceBase
{
private const string MqName = @".\private$\RequestQueue";
private static MessageQueue _mq;

private static MessageQueue mq
{
get
{
if (_mq == null)
{
if (!MessageQueue.Exists(MqName))
MessageQueue.Create(MqName);
_mq = new MessageQueue(MqName, QueueAccessMode.ReceiveAndAdmin);
_mq.Formatter = new BinaryMessageFormatter();
}
return _mq;
}
}
public Service1()
{
InitializeComponent();
mq.ReceiveCompleted += new ReceiveCompletedEventHandler(mq_ReceiveCompleted);
}

private void mq_ReceiveCompleted(object sender, ReceiveCompletedEventArgs e)
{

MessageQueue cmq = (MessageQueue)sender;
try
{
Message msg = cmq.EndReceive(e.AsyncResult);
}
catch
{
}
cmq.Refresh();
cmq.BeginReceive();
}

protected override void OnStart(string[] args)
{
while(mq != null)
mq.BeginReceive();
}
private void MsMq_ReceiveCompleted(object sender, ReceiveCompletedEventArgs e)
{
var msMq = (MessageQueue)sender;
var msg = msMq.EndReceive(e.AsyncResult);
msMq.BeginReceive();
}
protected override void OnStop()
{
if (mq != null)
mq.Close();
return;

}
}

Member 11837253 4-Apr-18 16:27pm

Windows service picking messages only when i start it and after that it stops listening

Christiaan van Bergen 4-Apr-18 16:34pm

You are not implementing the code I showed you. In your OnStart method use mq.Receive(), I also explained why you should use that method. Try it, if it still doesn't work, we'll take it from there.

Christiaan van Bergen 4-Apr-18 17:13pm

No, that's right. Because you need to do something with the actual message you're getting. Again, look at the example. It says: var msg = mq.Receive();
So do something with the message.