My WPF application has behaviour triggered by the functions keys (F1-F12).

My code is along these lines:

private void Window_KeyDown(object sender, KeyEventArgs e)
{
    switch (e.Key)
    {
        case Key.F1:
        ...
        case Key.F2:
        ...
    }
}

This works for all F-keys except F10. Debugging, I find that e.Key == Key.System when the user presses F10.

In the enum definition, F10 = 99 and System = 156, so I can rule out it being a duplicate enum value (like PageDown = Next = 20).

So, how do I tell when the user presses F10?

Is it safe to check for Key.System instead? This feels a little dirty - might it be possible that Key.System would ever result from some other key being pressed? Or is there some setting somewhere that will make F10 report as Key.F10?

wpf keyboard-events
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