Changing textbox content from inside the ThreadPool C#

Question

I am using a thread pool to do some tests, how can i change a Textbox.text in the form?

        ThreadPool.SetMaxThreads(3, 3);

        for(int i2 = 0; i2 < 100; i2++)
        {
            ThreadPool.QueueUserWorkItem(myInt, i2);
        }
        void myInt(object obj23)
    {
        int value = (int)obj23;
        writeTo(value);
       // code to write textbox1.text += value + "\n";
        Thread.Sleep(10000);

    }

error is because a thread that didnt create the object (textbox1) is trying to change it

just see here: http://stackoverflow.com/questions/519233/writing-to-a-textbox-from-another-thread — Davide Piras, Aug 29 '11 at 00:36
The error looks like the WPF error, not the winforms one. Is this WPF? — Chris Shain, Aug 29 '11 at 00:46
This code makes 0.0% sense given that controls can only be updated from the thread that created them. No point in pursuing it. — Hans Passant, Aug 29 '11 at 02:32

score 3 · Answer 1 · answered Aug 29 '11 at 00:45

Create a simple sample for you...

    private void Form1_Load(object sender, EventArgs e)
    {
        for (int i = 0; i < 100; i++)
        {
            System.Threading.ThreadPool.QueueUserWorkItem(k => {

                textBox2.Invoke(new Action(() => {
                    textBox2.AppendText("k:" + k + "\r\n");
                }));

            } , i);
        }
    }

Changing textbox content from inside the ThreadPool C#

1 Answers1