C# WPF数据绑定有问题吗

我有两个对象，一个客户和一个商店。有多个门店，每个客户都有一个名为PreferredStoreId（int？）的属性，该属性与门店Id（int？）相关

在WPF应用程序中，我试图构建一个允许编辑客户的表单。此表单上存在一个组合框，其中填充了存储，用作显示当前设置的PreferredStore和更改首选存储的方式

我的问题是，虽然我可以填充combobox，但我无法在Customer.PreferredId（设置为UserControl的datacontext的对象）和combobox的SelectedItem（存储对象）的.Id属性之间获得双向绑定

以下是我的XAML，有助于理解：

<UserControl x:Class="ucCustomerEditor"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
         xmlns:localViewModels="clr-namespace:ViewModels"
         xmlns:qc="clr-namespace:QuickConverter;assembly=QuickConverter"
         mc:Ignorable="d" d:DesignWidth="750" Height="334">
<UserControl.DataContext>
    <localViewModels:CustomerViewModel x:Name="customerViewModel" />
</UserControl.DataContext>
<StackPanel>
    <StackPanel Orientation="Horizontal" HorizontalAlignment="Right">
        <Button Height="26" Width="50" Content="Save" Margin="5,10" Click="UserAction_Save" />
        <Button Height="26" Width="50" Content="Cancel" Margin="10,10" Click="UserAction_Cancel" />
    </StackPanel>
    <Grid Height="26" Margin="10" VerticalAlignment="Top">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="209"/>
            <ColumnDefinition/>
        </Grid.ColumnDefinitions>
        <TextBox Text="{Binding FirstName}" Height="23" Margin="10,0,0,0" TextWrapping="Wrap" VerticalAlignment="Top" HorizontalAlignment="Stretch" Grid.Column="1"/>
        <Label Content="First Name:" Margin="10,0" VerticalAlignment="Top" FontWeight="Bold"/>
    </Grid>
    <Grid Height="26" Margin="10" VerticalAlignment="Top">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="209"/>
            <ColumnDefinition/>
        </Grid.ColumnDefinitions>
        <TextBox Text="{Binding LastName}" Height="23" Margin="10,0,0,0" TextWrapping="Wrap" VerticalAlignment="Top" HorizontalAlignment="Stretch" Grid.Column="1"/>
        <Label Content="Last Name:" Margin="10,0" VerticalAlignment="Top" FontWeight="Bold"/>
    </Grid>
    <Grid Height="26" Margin="10" VerticalAlignment="Top">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="209"/>
            <ColumnDefinition/>
        </Grid.ColumnDefinitions>
        <TextBox Text="{Binding EmailAddress}" Height="23" Margin="10,0,0,0" TextWrapping="Wrap" VerticalAlignment="Top" HorizontalAlignment="Stretch" Grid.Column="1"/>
        <Label Content="Email Address:" Margin="10,0" VerticalAlignment="Top" FontWeight="Bold"/>
    </Grid>
    <Grid Height="26" Margin="10" VerticalAlignment="Top">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="209"/>
            <ColumnDefinition/>
        </Grid.ColumnDefinitions>
        <TextBox Text="{Binding PhoneNumber}" Height="23" Margin="10,0,0,0" TextWrapping="Wrap" VerticalAlignment="Top" HorizontalAlignment="Stretch" Grid.Column="1"/>
        <Label Content="Phone Number:" Margin="10,0" VerticalAlignment="Top" FontWeight="Bold"/>
    </Grid>
    <Grid Height="26" Margin="10" VerticalAlignment="Top">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="209"/>
            <ColumnDefinition/>
        </Grid.ColumnDefinitions>
        <ComboBox Name="cbPreferredStore" 
                  ItemsSource="{Binding Stores}" DisplayMemberPath="DisplayName" Height="23" Margin="10,0,0,0" VerticalAlignment="Top" 
                  HorizontalAlignment="Stretch" Grid.Column="1" SelectedValue="{Binding ElementName=customerViewModel, Path=PreferredStoreId}">
            <ComboBox.DataContext>
                <localViewModels:StoreListViewModel />
            </ComboBox.DataContext>
        </ComboBox>
        <Label Content="Preferred Store:" Margin="10,0" VerticalAlignment="Top" FontWeight="Bold"/>
    </Grid>
    <Grid Height="26" Margin="10" VerticalAlignment="Top">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="209"/>
            <ColumnDefinition/>
        </Grid.ColumnDefinitions>
        <TextBox Text="{Binding Password}" Height="23" Margin="10,0,0,0" TextWrapping="Wrap" VerticalAlignment="Top" HorizontalAlignment="Stretch" Grid.Column="1"/>
        <Label Content="Password:" Margin="10,0" VerticalAlignment="Top" Height="26" FontWeight="Bold"/>
    </Grid>
</StackPanel>

StoreListViewModel代码：

public class StoreListViewModel : BaseViewModel
{
    private List<StoreViewModel> _stores;

    public List<StoreViewModel> Stores
    {
        get { return this._stores; }
        set
        {
            this._stores = value;
            notifyPropertyChanged("Stores");
        }
    }

    public StoreListViewModel()
    {
        EasyDayTea.EasyDayTeaClient client = new EasyDayTea.EasyDayTeaClient();
        _stores = client.GetStores(App.AppUserTeaCredental).Select(s => (StoreViewModel)s).ToList();
        client.Close();
    }
}

公共类StoreListViewModel:BaseViewModel
{
私家店铺名单;；
公共列表商店
{
获取{返回此。_存储；}
设置
{
这个。_存储=值；
通知财产变更（“存储”）；
}
}
public StoreListViewModel（）
{
EasyDayTea.EasyDayTeaClient=新的EasyDayTea.EasyDayTeaClient（）；
_stores=client.GetStores（App.appuserteacredent）。选择（s=>（StoreViewModel）s.ToList（）；
client.Close（）；
}
}

我认为CustomerServiceWModel中的

PreferredStoreId

属性正确实现了接口

如果为true，则需要将组合框的SelectedValue更改为

SelectedItem

，因为SelectedItem属性返回当前选定的整个对象。但是，属性和

SelectedValue

一起用作SelectedItem属性的替代，据我所知，这不是您的选择

这里也有：

SelectedValue="{Binding ElementName=customerViewModel, Path=PreferredStoreId}"

---

不需要ElementName，因为CustomServiceWModel设置了默认分配的

DataContext

。

您能显示

存储

属性的实现吗？您是否实现了INotifyPropertyChanged？您是否尝试从绑定中删除ElementName=CustomServiceWModel？我已将StoreListViewModel和StoreViewModel添加到原始帖子中。BaseViewModel实现INotifyPropertyChanged

SelectedValue="{Binding ElementName=customerViewModel, Path=PreferredStoreId}"