Passing data from datareceived to another thread

Last post was 12 Jul 2007 at 10:19

Ljubljana, Slovenia

- Reply
13 years ago

by GregaR

GregaR

, Slovenia

Joined 13 years ago
Hello all,

I am writting an application for windows CE 5.0 and i am trying to make it multithreaded.
The problem I am having is how to pass data from one thread to another...

This is what I have so far...
In a thread on main form I send a string of request to a Send function that is in module functions, then i want this thread to wait till the datareceived event that is in module functions fires up receives an answer on serial port and sends received data to thread which can then continue with its work...
Can someone please tell me how to do this if it is possible?.

Private Sub MeasureFlow()
        functions.send("SENDFLOW")
        'now this thread should wait for a reply from datareceived event....
        'when reply comes thread can continue...
End Sub

Thanks in advance
Bye

Report abuse
- Reply
13 years ago

by Mistuke

Mistaken Luke

The Netherlands, Netherlands

Joined 18 years ago
i usually do this through an implementation of the WaitQueue ADT,

i'm pasting a sample c# code, you need to convert it to VB.NET

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;
using System.Threading;

namespace System.Collections.Extra
{
    class WaitQueue<CType> : IDisposable
    {
        Queue<CType> data = new Queue<CType>();
        Semaphore sem = new Semaphore(0,1);
        Object __datadeq = new Object();
        Object __dataenq = new Object();

        public CType Dequeue()
        {
            lock (__datadeq)
            {
                if(this.data.Count == 0)
                    sem.WaitOne();

                return data.Dequeue();
            }
        }

        public void Enqueue(CType data)
        {
            lock (__dataenq)
            {
                this.data.Enqueue(data);
                if(this.data.Count==1)
                    sem.Release();
            }
        }

        public void Dispose()
        {
            sem.Close();
            this.data.Clear();
        }

    }
}

Report abuse
- Reply
13 years ago

by sanjay.gadge

Sanjay Gadge

Maharashtra, India

Joined 13 years ago
Use anonymous delegates to pass the data to new thread. Here is the code

public
class Logger : IDisposable

{

public
void Error(string message)
{

/// Create thread with anonymous delegate and pass LogEntry object to it
Thread
t = new Thread(delegate() { this.LogMessage(new LogEntry("EROR", message)); });
t.Start();

}

///
Thread entry point
private
void LogMessage(LogEntry dequed)
{

string logEntry = DateTime.Now.ToShortDateString() + ", " + dequed.Type + ", "+ dequed.Message;

}

}

Hope this helps.

-Sanjay Gadge

Report abuse
- Reply
13 years ago

by TwoFaced

Thomas Reynard

, United States

Joined 15 years ago
sanjay.gadge wrote:

Use anonymous delegates to pass the data to new thread. Here is the code

public
class Logger : IDisposable

{

public
void Error(string message)
{

/// Create thread with anonymous delegate and pass LogEntry object to it
Thread
t = new Thread(delegate() { this.LogMessage(new LogEntry("EROR", message)); });
t.Start();

}

///
Thread entry point
private
void LogMessage(LogEntry dequed)
{

string logEntry = DateTime.Now.ToShortDateString() + ", " + dequed.Type + ", "+ dequed.Message;

}

}

Hope this helps.

-Sanjay Gadge
Unfortunatly VB.net doesn't have anonymous delegates.

Report abuse
- Reply
13 years ago

by sanjay.gadge

Sanjay Gadge

Maharashtra, India

Joined 13 years ago
Sorry I do not know anything about VB/VB.Net.

But have a look at http://www.yoda.arachsys.com/csharp/threadstart.html. One of the technique here might be useful.

Cheers
Sanjay

Report abuse