获取ComboBox绑定多列列表的SelectedItem

Question

我有一个绑定到*.RData 的多列List。

它将列表列ComboBox显示为Name。

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问题

ItemSource确实返回SelectedItem。

对于Name，MessageBox.Show(vm.cboVideoQuality_SelectedItem);显示为string，而不是MyProgram.ViewModel+VideoQuality。

我尝试使用以下方法过滤High：
Name

但是它给出了错误vm.cboVideoQuality_SelectedItem.FirstOrDefault(s => s.Name);。

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XAML

绑定'char' does not contain definition for Name和Item Source。

Selected Item

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ViewModel

<ComboBox x:Name="cboVideoQuality" 

          ItemsSource="{Binding cboVideoQuality_Items, Mode=TwoWay}"
          DisplayMemberPath="Name"

          SelectedItem="{Binding cboVideoQuality_SelectedItem, Mode=TwoWay}"
          SelectedValuePath="Name"

          HorizontalAlignment="Left" 
          VerticalAlignment="Top" 
          Margin="0,0,0,0" 
          Width="100" />

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C＃

由于// Item Source // public class VideoQuality { public string Name { get; set; } public string Bitrate { get; set; } } public List<VideoQuality> _cboVideoQuality_Items = new List<VideoQuality>() { new ViewModel.VideoQuality() { Name = "High", Bitrate = "5000K" }, new ViewModel.VideoQuality() { Name = "Medium", Bitrate = "2500K" }, new ViewModel.VideoQuality() { Name = "Low", Bitrate = "500K" }, }; public List<VideoQuality> cboVideoQuality_Items { get { return _cboVideoQuality_Items; } set { _cboVideoQuality_Items = value; OnPropertyChanged("cboVideoQuality_Items"); } } // Selected Item // public string _cboVideoQuality_SelectedItem { get; set; } public string cboVideoQuality_SelectedItem { get { return _cboVideoQuality_SelectedItem; } set { if (_cboVideoQuality_SelectedItem == value) { return; } _cboVideoQuality_SelectedItem = value; OnPropertyChanged("cboVideoQuality_SelectedItem"); } } 不等于selected = "High"，我无法检查SelectedItem。

它等于Name。

MyProgram.ViewModel+VideoQuality

Answer 1

您已经使用过SelectedValuePath，当然也应该使用SelectedValue代替SelectedItem：

<ComboBox
      ItemsSource="{Binding cboVideoQuality_Items}"
      DisplayMemberPath="Name"
      SelectedValuePath="Name"
      SelectedValue="{Binding cboVideoQuality_SelectedItem}" .../>

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请注意，在两个绑定Mode=TwoWay中都是多余的。默认情况下，ItemsSource绑定不是双向的，而SelectedValue绑定是双向的。

我还建议不要在视图模型属性名称中使用绑定目标属性详细信息。例如。 cboVideoQuality_SelectedItem应该只是SelectedVideoQuality。因此，您也可以将其绑定到ListBox的SelectedValue属性，甚至是TextBlock的Text属性，而不会造成太多混乱。