How to read combobox from a thread other than the thread it was created on?

c# multithreading thread-safety invoke
nitrkli picture nitrkli · Apr 1, 2011 · Viewed 31.7k times · Source

I am trying to read a combobox.Text from a thread other than the thread it was created on but I am getting the error:

An unhandled exception of type 'System.InvalidOperationException' occurred in System.Windows.Forms.dll

Additional information: Cross-thread operation not valid: Control 'levelsComboBox' accessed from a thread other than the thread it was created on.

I have used .Invoke before but only to set properties, how can I use it to read combobox.Text? Because .Invoke returns void and I need a string. Or is there another way to do it without the Invoke?

Answer

BrandonZeider picture BrandonZeider · Apr 1, 2011

You can do it like this:

this.Invoke((MethodInvoker)delegate()
    {
        text = combobox.Text;
    });

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