TUM.CMS.VplControl.Core.SelectionNode.searchTextBox_KeyDown C# (CSharp) Method

        private void searchTextBox_KeyDown(object sender, KeyEventArgs e)
        {
            var textBox = sender as SearchTextBox;

            if (e.Key == Key.Enter && listBox.Items.Count > 0)
            {
                if ((textBox != null && textBox.Text != "") ||
                    (listBox.SelectedIndex > -1 && listBox.SelectedIndex < listBox.Items.Count + 1)
                    )
                    CreateNode();
                else
                {
                    Hide();
                }
            }
            else
            {
                switch (e.Key)
                {
                    case Key.Down:
                        if (listBox.SelectedIndex < listBox.Items.Count)
                        {
                            listBox.SelectedIndex += 1;
                            e.Handled = true;
                        }
                        break;
                    case Key.Up:
                        if (listBox.SelectedIndex > 0) listBox.SelectedIndex -= 1;
                        e.Handled = true;
                        break;
                }
            }
        }