To achieve this, you must use e.SuppressKeyPress = True in your event handler.
Greetings
Kyle
EDIT: My mistake, sorry.
Ok, then you could make your catch code for your F keys to e.Handled = true, which should clear the WM_Chars queue, which means that the main control will not receive the event. Also, look at the WPF commands to work this way. I do not know a very "clean" solution to this problem. Unfortunately.
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