我应该如何只在WPF中选中一个复选框？

Question

我对使用WPF中的数据绑定不是很熟悉。请看看我的代码。我想限制用户只做一个选择。

更常见的问题是：我应该如何避免循环数据源，因为我已经在handleChecked方法中做了什么？我相信我不需要通过ItemSource循环，但不知道如何。

的XAML：

<Window x:Class="TheProgram.MainWindow" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    Title="News Chooser"> 
<Grid> 
    <Grid.RowDefinitions> 
     <RowDefinition Height="9*" /> 
     <RowDefinition Height="1*" /> 
    </Grid.RowDefinitions> 
    <Grid Name="newsChooser" Grid.Row="0" Margin="10"> 
     <Grid.RowDefinitions> 
      <RowDefinition Height="Auto" /> 
      <RowDefinition Height="Auto" /> 
      <RowDefinition Height="8*" /> 
     </Grid.RowDefinitions> 
     <ComboBox Name="newsCategory" Margin="10,8,10,5" Grid.Row="0"/> 
     <ComboBox Name="newsSrc" SelectionChanged="handleNewsSrcChange" Margin="10,5,10,8" Grid.Row="1"/> 
     <DataGrid SelectionMode="Single" IsReadOnly="True" Margin="10,0,10,8" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Grid.Row="2" Name="newsStories" AutoGenerateColumns="False" RowHeaderWidth="0"> 
      <DataGrid.Columns> 
       <DataGridTextColumn Width="8*" Header="Headline" Binding="{Binding Path=heading}"> 
        <DataGridTextColumn.HeaderStyle> 
         <Style TargetType="DataGridColumnHeader"> 
          <Setter Property="HorizontalContentAlignment" Value="Center" /> 
         </Style> 
        </DataGridTextColumn.HeaderStyle> 
        <DataGridTextColumn.ElementStyle> 
         <Style> 
          <Setter Property="TextBlock.TextWrapping" Value="Wrap" /> 
          <Setter Property="TextBlock.Padding" Value="5" /> 
         </Style> 
        </DataGridTextColumn.ElementStyle> 
       </DataGridTextColumn> 
       <DataGridCheckBoxColumn Header="Select" Width="2*" Binding="{Binding Path=isIncluded, Mode=OneWayToSource, UpdateSourceTrigger=PropertyChanged}"> 
        <DataGridCheckBoxColumn.HeaderStyle> 
         <Style TargetType="DataGridColumnHeader"> 
          <Setter Property="HorizontalContentAlignment" Value="Center" /> 
         </Style> 
        </DataGridCheckBoxColumn.HeaderStyle> 
        <DataGridCheckBoxColumn.ElementStyle> 
         <Style> 
          <Setter Property="TextBlock.HorizontalAlignment" Value="Center" /> 
          <Setter Property="TextBlock.VerticalAlignment" Value="Center" /> 
         </Style> 
        </DataGridCheckBoxColumn.ElementStyle> 
        <DataGridCheckBoxColumn.CellStyle> 
         <Style> 
          <EventSetter Event="CheckBox.Checked" Handler="handleChecked" /> 
          <EventSetter Event="CheckBox.Unchecked" Handler="handleChecked" /> 
         </Style> 
        </DataGridCheckBoxColumn.CellStyle> 
       </DataGridCheckBoxColumn> 
      </DataGrid.Columns> 
     </DataGrid> 
    </Grid> 
    <StackPanel Grid.Row="1" Grid.ColumnSpan="2" Orientation="Horizontal" Margin="20,0,10,0"> 
     <Button Click="handleSendButton" Height="30" Width="70">Send</Button> 
    </StackPanel> 
</Grid> 

代码背后：

namespace TheProgram 
{ 

class NewsSrcTableItm 
{ 
    public string heading { get; set; } 
    public NewsItem itm { get; set; } 
    public bool isIncluded { get; set; } 
} 

public partial class MainWindow : Window 
{ 

    private List<NewsItem> includedList = null; 

    public MainWindow() 
    { 
     InitializeComponent(); 
     setNewsSourceComboBox(); 

     this.includedList = new List<NewsItem>(); 

     initializeNewsTable(); 
    } 

    private void setNewsSourceComboBox() 
    { 
     ComboBox cbx = (ComboBox)this.FindName("newsSrc"); 
     cbx.ItemsSource = MainWinClass.comboBoxList(); 
     cbx.SelectedIndex = 0; 

     ComboBox cbx1 = (ComboBox)this.FindName("newsCategory"); 
     cbx1.ItemsSource = MainWinClass.categoryList(); 
     cbx1.SelectedIndex = 0; 
    } 

    private void initializeNewsTable() 
    { 
     newsStories.ItemsSource = MainWinClass.initializeNewsSource(); 
    } 


    public void handleChecked(object sender, RoutedEventArgs e) 
    { 
     ComboBox cbx = this.FindName("newsCategory") as ComboBox; 
     String theSelected = Regex.Replace(cbx.SelectedValue.ToString(), " ", String.Empty); 
     String theNewsCategory = char.ToLower(theSelected[0]) + theSelected.Substring(1); 
     foreach (var r in newsStories.ItemsSource) 
     { 
      NewsSrcTableItm itm = (NewsSrcTableItm)r; 
      if (itm.isIncluded) 
      { 
       if (itm.itm.getCategory() == null) 
       { 
        itm.itm.setCategory(theNewsCategory); 
       } 
       this.includedList.Add(itm.itm); 
      } 
     } 
    } 

    public void handleNewsSrcChange(object Sender, EventArgs args) 
    { 
     ComboBox cb = this.FindName("newsSrc") as ComboBox; 
     newsStories.ItemsSource = MainWinClass.changeSource(cb.SelectedValue.ToString()); 
    } 

    public async void handleSendButton(object Sender, EventArgs args) 
    { 
     NewsItem itm = this.includedList[0]; 
     String category = itm.getCategory(); 
     String title = itm.getHeading(); 
     String extract = null; 
     String content = null; 
     String timestamp = DateTime.Now.ToString("yyyyMMdd"); 
     NewsContentFetcher f = new NewsContentFetcher(itm.getUrl()); 
     List<String> theList = await f.getContent(); 
     extract = theList[0]; 
     foreach (String s in theList) 
     { 
      content += s; 
     } 
     HttpClient client = new HttpClient(); 
     var values = new Dictionary<String, String> 
     { 
      { "category", category }, 
      { "title", title }, 
      { "extract", extract }, 
      { "content", content }, 
      { "timestamp", timestamp } 
     }; 
     var theContent = new FormUrlEncodedContent(values); 
     var result = client.PostAsync("http://localhost/addNews.php", theContent).Result; 
     int statusCode = (int)result.StatusCode; 
     if (statusCode == 200) 
     { 
      MessageBox.Show("Completed"); 
     } 
     else 
     { 
      MessageBox.Show("failed"); 
     } 
    } 

} 
} 

Answer 1

但反正是有直接将选中的复选框指数，这样我可以修改给出的绑定数据索引？

试试这个：

public void handleChecked(object sender, RoutedEventArgs e) 
{ 
    CheckBox chk = e.OriginalSender as CheckBox; 
    NewsSrcTableItm itm = chk.DataContext as NewsSrcTableItm; 

    //get index: 
    var sourceCollection = newsStories.ItemsSource as IList<NewsSrcTableItm>; 
    int index = sourceCollection.IndexOf(itm); 
    //... 
}