Microsoft.Windows.Controls.Ribbon.RibbonMenuButton.OnKeyUp C# (CSharp) Метод

        protected override void OnKeyUp(KeyEventArgs e)
        {
            if (!IsDropDownOpen && HandleSpaceEnterUp)
            {
                if (e.OriginalSource == this ||
                    e.OriginalSource == _partToggleButton)
                {
                    if (e.Key == Key.Space ||
                        e.Key == Key.Enter)
                    {
                        IsDropDownOpen = true;
                        RibbonHelper.NavigateToNextMenuItemOrGallery(this, -1, BringIndexIntoView);
                        e.Handled = true;
                    }
                }
            }
            HandleSpaceEnterUp = false;
            base.OnKeyUp(e);
        }