Question

这里我将通过wpf中的数据表绑定组合框但是在fornt end中没有显示值的组合框可以任何人告诉它有什么问题。还有代码

//XAML
<ComboBox Canvas.Left="148" Canvas.Top="62" Height="23" 
          Name="cmbGameProfile" Width="217" 
          ItemsSource="{Binding Path=PROFILE_NAME}" 
          DisplayMemberPath="PROFILE_NAME"  />     

//Code-behind
public static void GameProfileList(ComboBox ddlCategoryType)
{
    try
    {
            DataTable dtGameProfileList = null;   
            try
            {
                ClsDataLayer objDataLayer = new ClsDataLayer();
                objDataLayer.AddParameter("@REF_USER_ID",0);
                dtGameProfileList = objDataLayer.ExecuteDataTable("COMNODE_PROC_GetGameProfile");
                if (dtGameProfileList != null && dtGameProfileList.Rows.Count > 0)
                {
                    ddlCategoryType.DataContext = dtGameProfileList;
                    ddlCategoryType.DisplayMemberPath = dtGameProfileList.Rows[0]["PROFILE_NAME"].ToString();
                    ddlCategoryType.SelectedValuePath = dtGameProfileList.Rows[0]["PROFILE_ID"].ToString();
                }
            }
            catch (Exception)
            {
                throw;
            }                                  
    }
    catch
    {
    }
}

Answer 1

如果我理解得好PROFILE_NAME只是结果中的一栏。当ItemsSource绑定属性PROFILE_NAME时，需要将其设置为某个IEnumerable。您需要将其设置为DataTable的某些视图，以便

ddlCategoryType.ItemsSource = dtGameProfileList.DefaultView;

或

ddlCategoryType.ItemsSource = new DataView(dtGameProfileList);

Answer 2

考虑到WPF将在渲染发生之前尝试创建绑定，您可能需要考虑使用ObservableCollection。

在你的xaml中，你会将ItemsSource更新为ItemsSource =＆＃34; {Binding YourClassInstanceMember}＆＃34;然后在GameProfileList（..）中，您将非可观察集合类转换为ObservableCollection并将其分配给您的后备字段（随后将通知UI进行更新）。

一些推荐阅读

[数据绑定概述] http://msdn.microsoft.com/en-us/library/ms752347(v=vs.110).aspx

[INotifyPropertyChanged的]

http://msdn.microsoft.com/en-us/library/vstudio/system.componentmodel.inotifypropertychanged

在伪代码中..

<Window xmlns:vm="clr-namespace:YourProject.YourViewModelNamespace">
    <Window.DataContext>
        <vm:YourViewViewModel />
    </Window.DataContext>
    <ComboBox ItemsSource="{Binding GameProfileListItems}"/>
</Window>

public class YourViewViewModel : ViewModelBase (this is something that implements INotifyPropertyChanged)
{
    ObservableCollection<string> _gameProfileListItems;
    ObservableCollection<string> GameProfileListItems
    {
        get { return _gameProfileListItems; }
        set { _gameProfileListItems = value; OnPropertyChanged("GameProfileListItems"); }
    }

    public void SetGameProfileListItems()
    {
        //    go and get your data here, transfer it to an observable collection
        //    and then assign it to this.GameProfileListItems (i would recommend writing a .ToObservableCollection() extension method for IEnumerable)
        this.GameProfileListItems = SomeManagerOrUtil.GetYourData().ToObservableCollection();
    }
}

public class YourView : Window
{
    public void YourView()
    {
        InitializeComponent();

        InitializeViewModel();
    }

    YourViewViewModel ViewModel
    {
        { get return this.DataContext as YourViewViewModel; }
    }

    void InitializeViewModel()
    {
        this.ViewModel.SetGameProfileListItems();
    }
}

Combobox没有在wpf中显示值

2 个答案: