private void TextBox_PreviewKeyDown(object sender, KeyEventArgs e) { if ((e.Key == Key.Tab) || (e.Key == Key.Right)) { _tabHelper = new TabNavigationHelper(resultsTv); TextBox next = _tabHelper.GoRight((TextBox)sender); if (next != null) { next.Focus(); e.Handled = true; } } else if (e.Key == Key.Left) { _tabHelper = new TabNavigationHelper(resultsTv); TextBox next = _tabHelper.GoLeft((TextBox)sender); if (next != null) { next.Focus(); e.Handled = true; } } else if (e.Key == Key.Down) { _tabHelper = new TabNavigationHelper(resultsTv); TextBox next = _tabHelper.GoDown((TextBox)sender); if (next != null) { next.Focus(); e.Handled = true; } } else if (e.Key == Key.Up) { _tabHelper = new TabNavigationHelper(resultsTv); TextBox next = _tabHelper.GoUp((TextBox)sender); if (next != null) { next.Focus(); e.Handled = true; } } }