public void ProcessKeyUpEvent(KeyEventArgs e) { switch (e.Key) { case Key.LeftAlt: case Key.RightAlt: isAltDown = false; break; case Key.LeftCtrl: case Key.RightCtrl: isControlDown = false; break; case Key.LeftShift: case Key.RightShift: isShiftDown = false; break; case Key.Left: case Key.Right: case Key.Up: case Key.Down: ContentGrid.ProcessArrowRelease(); break; default: break; } switch ((ModifierKeys)e.Key) { case ModifierKeys.Alt: isAltDown = false; break; case ModifierKeys.Control: isControlDown = false; break; case ModifierKeys.Shift: isShiftDown = false; break; } }