My problem with form freeze for secend and execute

Question

I tried a lot: Thread, DoWork, Async Await, but I got the error:

System.InvalidOperationException: 'Cross-thread operation not valid: Control 'combo' accessed from a thread other than the thread it was created on.'

Here is my code:

 public void ggggg()
    {
        var Names = combo.Text;
        string[] strArray = Regex.Split(Names, " - ");
        var port = Convert.ToString(strArray[0]);
        if (port == "")
        {
            MessageBox.Show("Please Selcet ", "Info", MessageBoxButtons.OK, MessageBoxIcon.Information);
            return;
        }
        else
        {

            MessageBox.Show("Done", "Info", MessageBoxButtons.OK, MessageBoxIcon.Information);

        }
    }


     private void BtnNames_Click(object sender, EventArgs e)
     {
    Thread y = new Thread(delegate () { ggggg(); });
       y.Start();

     }

Another part of the code:

var Names = this.Invoke(new MethodInvoker(delegate { combo.Text = combo.Text.Text + ""; }));;

I think My ques not clear what i need how i can run thread without problem when i execute < System.InvalidOperationException> — Helal Rajeh, Nov 16 '19 at 19:00
Why not do everything needing access to UI controls in `BtnNames_Click` and passing the collected data (in you case `Names`) to the background thread as parameter? — Klaus Gütter, Nov 16 '19 at 19:25
Move `var Names = combo.Text;` to `BtnNames_Click` and pass Names as parameter to `ggggg(Names)`. — Klaus Gütter, Nov 16 '19 at 19:31
I get error No overloaded for method 'ggggg' takes one arguments — Helal Rajeh, Nov 16 '19 at 19:44
Check [How do I update the GUI from another thread?](https://stackoverflow.com/questions/661561/how-do-i-update-the-gui-from-another-thread) and [Updating Windows Form UI elements from another thread](https://blogs.msdn.microsoft.com/make_it_better/2017/05/15/updating-windows-form-ui-elements-from-another-thread/) — , Nov 16 '19 at 20:25

score 0 · Answer 1 · answered Nov 16 '19 at 20:26

0

Not sure if I understood you correctly, but you may try out this:

public string ggggg(string Names)
{
    string[] strArray = Regex.Split(Names, " - ");
    return Convert.ToString(strArray[0]);
}


public async void BtnNames_Click(object sender, EventArgs e)
{
    var names = combo.Text;
    var port = await Task.Run(() => ggggg(names));

    if (port == "")
    {
        MessageBox.Show("Please Selcet ", "Info", MessageBoxButtons.OK, MessageBoxIcon.Information);
    }
    else
    {
        MessageBox.Show("Done", "Info", MessageBoxButtons.OK, MessageBoxIcon.Information);
    }
}

answered Nov 16 '19 at 20:26

Welcor

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I execute the code but still freezing i don't now why? I don't have any error why freezing... – Helal Rajeh Nov 17 '19 at 15:26
Any one know what's my problem – Helal Rajeh Nov 18 '19 at 13:01

score 0 · Accepted Answer · answered Nov 18 '19 at 17:25

I just add one code before If and work perfect thanks guys

public string ggggg(string Names)
{
string[] strArray = Regex.Split(Names, " - ");
return Convert.ToString(strArray[0]);
}
public async void BtnNames_Click(object sender, EventArgs e)
{
var names = combo.Text;
var port = await Task.Run(() => ggggg(names));
await Task.Factory.StartNew(() => // I add this code

if (port == "")
{
    MessageBox.Show("Please Selcet ", "Info", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
else
{
    MessageBox.Show("Done", "Info", MessageBoxButtons.OK, MessageBoxIcon.Information);
}

}

My problem with form freeze for secend and execute

2 Answers2