Multithreading in C# with Win.Forms control

Question

I\'m beginner in C#. And i have problem with threads when i using win.forms. My application freezes. What the problem with this code? I\'m using microsoft example from msdn. Her

Answer 1

It freezes because of the Join calls. Thread.Join() makes the current thread wait after another one is complete.

Answer 2

There is a deadlock - UI thread is waiting for threads to complete with Thread.Join() while the worker threads are trying to send a message to UI using blocking Control.Invoke(). Replacing the Invoke in the thread code by BeginInvoke() will make the deadlock go away

 if (this.textBox1.InvokeRequired)
    {
        SetTextCallback d = new SetTextCallback(WriteString);
        // BeginInvoke posts message to UI thread asyncronously
        this.BeginInvoke(d, new object[] { text }); 
    }
    else
    {
        this.textBox1.Text = text.ToString();
    }