protected void Gc_KeyPress(object sender, GLKeyEventArgs e)
 {
     if (currentfocus != null && currentfocus.Enabled)
     {
         if (!(currentfocus is GLForm))
         {
             currentfocus.FindForm()?.OnKeyPress(e);         // reflect to form
         }
         if (!e.Handled)
         {
             currentfocus.OnKeyPress(e);                     // send to control
         }
     }
     else
     {
         OnKeyPress(e);
     }
 }