在Silverlight中使用textbox实现下拉列表

 public void GetShow(TextBox txtBox,List<FontFamily> font)
        {
            Popup p = new Popup();
            Border border = new Border();
            border.BorderBrush = new SolidColorBrush(Colors.Blue);
            border.BorderThickness = new Thickness(0);

            StackPanel panel1 = new StackPanel();
            panel1.Background = new SolidColorBrush(Colors.White);

            ListBox list = new ListBox();            list.Height = 100;            list.Width = txtBox.Width;            list.ItemsSource = font;            list.SelectionChanged += new SelectionChangedEventHandler((sender,e) =>   //添加选择到textBox空间上            {                    txtBox.Text = list.SelectedItem.ToString();                    panel1.Width = txtBox.Width;                    if (txtBox.Text != "" || txtBox.Text != null)                        p.IsOpen = false;            });            panel1.Children.Add(list);            border.Child = panel1;            p.Child = border;            p.VerticalOffset = txtBox.Margin.Top + txtBox.Height;   //让创建的面板始终都在textBox空间的下方            p.HorizontalOffset =txtBox.Margin.Left;            p.IsOpen = true;        }