I have a Form that throws this when I close it:
"Invoke or BeginInvoke cannot be called on a control until the window handle has been created."

This seems to be the offending code, running in a child thread:

this.Invoke(new someDelegate(someMethod));

I figured that if I could capture the user clicking on the X in the window chrome I could stop this thread before it tries calling the (already closed) Main thread. I'm not finding anything useful by googling, which keywords should I be searching for? What am I doing wrong? Should I just wrap it in a try{}?

Thanks!

You can use an even FormClosing. Create this event on form creation, and when you will try to exit form, the event formClosing will be rised:

public Form1()
        {
            InitializeComponent();
            this.FormClosing+=new FormClosingEventHandler(Form1_FormClosing);
        }

        private void Form1_FormClosing(object sender, FormClosingEventArgs e)
        {
            //here you do the code!
        }

btw, for which control do you use delegate for invoke it? If you wont salve the problem, please feel free to paste some of the code in here - so I can be in a bigger help.
Mitja

Thank you Mitja, that is just what I need. The delegate is just to some TCP handler, nothing that will get clobbered by closing uncleanly.

Have a great day!

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