C# - How to make this thread wait?

Question

I have this:

public class ServiceLibrary
{
    public object result = null;
    private bool finished = false;

    public void testar()
    {
       ServiceReference.Service1SoapClient serviceReference = new ServiceReference.Service1SoapClient();
       serviceReference.updateUserCompleted += new EventHandler<ServiceReference.updateUserCompletedEventArgs>(serviceReference_updateUserCompleted);
       serviceReference.updateUserAsync();
       ManualResetEvent m = new ManualResetEvent(true);

    }

    void serviceReference_updateUserCompleted(object sender, ServiceReference.updateUserCompletedEventArgs e)
    {
        result = e.Result;
        finished = true;
    }
}

and outside I have this:

public Home()
{
    InitializeComponent();

    ServiceLibrary serviceLibrary = new ServiceLibrary();
    serviceLibrary.testar();
    lblCharName.Text = Convert.ToString(serviceLibrary.result);

}

What should I do to the thread wait, so when I asign the text, it contains the value, please? Thank you

Answer 1

I have a similar situation. I use a technique called polling, which is exactly what it sounds like. It may or may not be appropriate for you depending on your situation.

public class ServiceLibrary
{
public object result = null;
private bool finished = false;

public void testar()
{
   ServiceReference.Service1SoapClient serviceReference = new ServiceReference.Service1SoapClient();
   serviceReference.updateUserCompleted += new EventHandler<ServiceReference.updateUserCompletedEventArgs>(serviceReference_updateUserCompleted);
   serviceReference.updateUserAsync();
   ManualResetEvent m = new ManualResetEvent(true);

while !finished
 Thread.Sleep(100);

doStuffWithResult(result);
}

void serviceReference_updateUserCompleted(object sender, ServiceReference.updateUserCompletedEventArgs e)
{
    result = e.Result;
    finished = true;
}

Answer 2

Make your ManualResetEvent variable m a member variable of the class. and inside your threaded method: serviceReference_updateUserCompleted, make sure to call m.WaitOne();

Answer 3

What about

public class ServiceLibrary
{
  public object result = null;

  public void testar()
  {
     var serviceReference = new ServiceReference.Service1SoapClient();
     using(var m = new ManualResetEvent(false))
     {
       Action<object, ServiceReference.updateUserCompletedEventArgs> handler = 
       (sender, e) => 
       {
         result = e.Result;
         m.Set();
       };
       serviceReference.updateUserCompleted += handler;
       serviceReference.updateUserAsync();
       m.WaitOne();
       serviceReference.updateUserCompleted -= handler;
     }
  }
}