開始很簡單的學了xmal代碼如下:但是報錯,不知道爲什麼?
<ComboBox HorizontalAlignment="Left" VerticalAlignment="Bottom" x:Name="abc" SelectionChanged="abc_SelectionChanged">
<ComboBoxItem Content="1" IsSelected="True" />
<ComboBoxItem Content="2" />
<ComboBoxItem Content="3" />
</ComboBox>
在代碼中獲取值是報錯的:ComboBoxItem item = abc.SelectedItem as ComboBoxItem;
txt.Text = item.Content.ToString();
修改代碼:不需要 IsSelected="True"也不需要 ItemsSource="{Binding}"纔可以運行,但是我又想啓動選擇第二項。。。怎麼辦
然後再cs代碼中通過abc.SelectedIndex = 2;纔有用,哎......
下面看看整個代碼吧,很亂,一個是xmal初始內容數據,一個是綁定列表對象:
xmal如下:
<Grid x:Name="LayoutRoot" Background="White" Height="228" Width="378">
<ComboBox x:Name="cbbTest" Height="30" Width="100" ItemsSource="{Binding}" DisplayMemberPath="Id" SelectionChanged="select"/>
<TextBlock Height="30" Width="100" HorizontalAlignment="Center" VerticalAlignment="Bottom" x:Name="txt"></TextBlock>
<ComboBox HorizontalAlignment="Left" VerticalAlignment="Bottom" x:Name="abc" SelectionChanged="abc_SelectionChanged">
<ComboBoxItem Content="1" />
<ComboBoxItem Content="2" />
<ComboBoxItem Content="3" />
</ComboBox>
</Grid>
cs.如下:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
namespace Combombox
{
public partial class MainPage : UserControl
{
public MainPage()
{
InitializeComponent();
getData();
abc.SelectedIndex = 2;
}
List<Class1> lstSource = new List<Class1>();
private void getData() {
lstSource.Add(new Class1 { Id="1",Name="oracle"});
lstSource.Add(new Class1 { Id = "2", Name = "java" });
lstSource.Add(new Class1 { Id = "3", Name = "linux" });
lstSource.Add(new Class1 { Id = "4", Name = "windows 8" });
cbbTest.ItemsSource = lstSource;
cbbTest.SelectedIndex = 0;
}
private void select(object sender, SelectionChangedEventArgs e)
{
string selectedId = (cbbTest.SelectedItem as Class1).Name;
txt.Text = selectedId;
}
private void abc_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
ComboBoxItem item = abc.SelectedItem as ComboBoxItem;
txt.Text = item.Content.ToString();
}
}
}
數據類如下:
namespace Combombox
{
public class Class1
{
public string Name { get ;set;}
public string Id { get; set; }
}
}
最後給出效果吧: