Question

I´m developing a software in C# that uses static functions from a C++ .dll file through a Wrapper.

The problem is that some of these functions are slow and unstable, so in order to solve this I created a Thread that executes them. However, when I abort that thread from the main thread, the program isn´t letting me use those functions again, even though I define a new instance of the thread every time I call a function.

Is there any way I can fix this?

Thanks in advance.

PS: Here is some code from my program:

public partial class MainForm : Form, IMultiLanguage
{
      //...

      //This method is subscribed to the event of pressing the 'Abort' button
      private void StopCurrentAnalisis()
      {
            try
            {
                this.analisisManagerController.AnalisisThread.Abort();
            }
            catch (Exception e){  }
            finally
            {
                MessageBox.Show("Analisis has been cancelled by user", "Analisis Interrupted", MessageBoxButtons.OK, MessageBoxIcon.Stop);
                CerrarNowLoadingForm();
            }
      }

      //..
}

public class AnalisisManager: IAnalisisManagerController
{
    //..
    private Thread analisisThread;
    public Thread AnalisisThread{get{return this.analisisThread;}}


    public void MakePadrobAnalisis(TipoAnalisis tipoAnalisis,
        Dictionary<string, Dictionary<int, double>> parametros)
    {
        object[] arregloParams = new object[]{tipoAnalisis,parametros};
        analisisThread = new Thread(new ParameterizedThreadStart(MakeAnalisisInOtherThread));
        analisisThread.Start(arregloParams);
    }

 private void MakeAnalisisInOtherThread(object o)
    {
        object[] arregloParams = o as object[];
        TipoAnalisis tipoAnalisis = (TipoAnalisis) arregloParams[0];
        Dictionary<string, Dictionary<int, double>> parametros = arregloParams[1] as Dictionary<string, Dictionary<int, double>>;

        //This launches an event telling the GUI the unstable analisis has started.
        //The method that makes the 'Abort' button to appear on the GUI is subscribed to this event
        StartAnalisis();

       //The Thread executes DLL functions according to tipoAnalisis, for example:
       case InvKinematicsMinTorque:
       {
           WrapperPadirob.InverseKinematicsMinTorqueConfigAnalisis();
           break;
       }
       //..
   }
}

Answer 1

However, when I abort that thread
from the main thread

That’s your problem. You should not be using Thread.Abort. Check out “Non-Evil Cancellation” in this article for a better approach. From there …

The approach I always recommend is
dead simple. Have a volatile bool
field that is visible both to your
worker thread and your UI thread. If
the user clicks cancel, set this flag.
Meanwhile, on your worker thread, test
the flag from time to time. If you see
it get set, stop what you’re doing.

Also, very good discussion of this in this SO thread.

Per comment:

You own this thread …

Thread AnalisisThread{get{return this.analisisThread;}}

… it executes a delegate pointing to …

private void MakeAnalisisInOtherThread(object o)

… you also own that method. If the C++ interface does not have a reasonable .StopAnalysis method (or something similar), you must wait until the analysis is done and then poll the main thread as discussed in the articles. Blowing up your thread to stop the analysis is not the right thing to do.