void _formChrome_NonClientMouseDown(object sender, NonClientMouseEventArgs e)
{
var state = new ButtonStates(this);
if (state.OverButton != ChromeButton.None || state.OverExtraButton != null)
{
_formChrome.BeginUpdate();
SetOverButton(ChromeButton.None);
SetOverButton(null);
SetDownButton(state.OverButton);
SetDownButton(state.OverExtraButton);
CaptureStart = e.Location;
Form.Capture = true;
_formChrome.EndUpdate();
}
}