Question

I have an issue with my current .net application and is the follow, when a database row is updated or a new row is inserted, my .net service has to read those changes and submit an print order.

I’d implemented the follow functions :

public void OnStart()
{
   ThreadMgmt pthread = new ThreadMgmt();
   pthread.printNotification += new pthread.DatabaseChanged();
   pthread.frequency = 2000;

   ThreadStart ts = new ThreadStart(pthread.Wait);
   Thread t = new Thread(ts);

   t.Start();
}

void ReadDataBase() {...}

void Printing(){...}

public class ThreadMgmt 
{
  public delegate void UpdateDelegate();

  public event UpdateDelegate Notify;

  private int frequency {set;get;}


     public void Wait()
     {
        for (int i = 0; i <= Freq; i++)
        {
           Thread.Sleep(this.frequncy);
           Notify();
        }
     }
}

But I need some help about concepts about threading and looping events, I would like to know if anybody has to face the same problem and how to resolve it…

Thanks

Answer 1

Here’s a simple solution.

     private bool m_stop;
     public void Stop ()
     {
        lock (this)
           m_stop = true;
     }

     public void Wait()
     {
        for (int i = 0; i <= Freq; i++)
        {
           lock (this)
           {
              if (m_stop)
                 return;
           }
           Thread.Sleep(this.frequncy);
           if (Notify != null)
              Notify();
        }
     }

If you want shutdown to occur quicker, you can use Monitor.Wait and Monitor.PulseAll, but you should read up on these before you decide to do it.