Wpf DataContext不工作

我有一个带有组合框和两个文本框的表单。在我的XAML中，我设置了一个资源，如下所示：

 <Window.Resources>
    <DataTemplate x:Key="myTemplate">
        <StackPanel Orientation="Horizontal">
            <TextBlock Text="{Binding Path=First}" />
            <TextBlock Text=" " />
            <TextBlock Text="{Binding Path=Last}" />
        </StackPanel>
    </DataTemplate>
</Window.Resources>

我有两个问题。首先，combobox是空的，尽管我可以确认taEmployees确实包含正确的数据。其次，我得到两个文本框的错误消息，路径无效。然而，相同的路径对myTemplate有效

---

错误在哪里？

我认为自动从TableAdapter中提取数据还不够神奇，请尝试以下DataContext=dsTest.Employees；哪个是满桌的，宾果！谢谢金刚。

<ComboBox Name="theCombo" 
    IsSynchronizedWithCurrentItem="True"  
    ItemsSource="{Binding}" 
    ItemTemplate="{StaticResource myTemplate}" />

</Canvas.Resources>
    <TextBlock Canvas.Top="5">First Name:</TextBlock>
    <TextBox Canvas.Top="5" Text="{Binding Path=First}" />
    <TextBlock Canvas.Top="25">Last Name:</TextBlock>
    <TextBox Canvas.Top="25" Text="{Binding Path=Last}" />
</Canvas>

Dim dsTest As TestDataSet = New TestDataSet

Private Sub Window_Loaded(sender As Object, e As RoutedEventArgs)
    Dim taEmployees As TestDataSetTableAdapters.EmployeesTableAdapter = New TestDataSetTableAdapters.EmployeesTableAdapter
    taEmployees.Fill(dsTest.Employees)
    DataContext = taEmployees
 End Sub