在组合框中显示来自外部键约束的名称 [英] Display name from foreign Key constraint within a combobox

问题描述

我有三个表。 Employee，ClientEmp和Client。

ClientEmp拥有员工（EmployeeID）和客户（ClientID）的 ForeignKey 。

到目前为止，我能够在我的数据库中保存对ClientEmp的更改（使用 EF ）， code> selected 客户端。但是我必须在文本框中手动输入EmployeeID ForeignKey 才能匹配数据以保存。

显然，如果用户不知道EmployeeID FK是如何输入到文本框 $ c>。

因此，是否有办法使用组合显示Employee Firstname的列表框，然后保存到数据库？

我试过这个，但似乎不工作。 / p>

 < ComboBox Grid.Column =1Grid.Row =1Name =cbEmployeeName
 ItemsSource ={Binding Source = {StaticResource Employee}}
 DisplayMemberPath =FirstName
 SelectedValuePath =EmployeeID> 
< / ComboBox> 
  

我也试过使用此链接和此链接在这里帮助但没有效果。

解决方案

最后，我通过 WPF聊天室的帮助找到了帮助，并帮助从 Maverik 。

在我的xaml中，我定义了以下内容：

 < ResourceDictionary> 
< ObjectDataProvider x：Key =Employee
 ObjectType ={x：Type vm：ClientBookKeepingViewModel}
 MethodName =GetEmp> 
< / ObjectDataProvider> 
< / ResourceDictionary> 
 
< ComboBox Grid.Column =1Grid.Row =1Name =cbEmployeeName
 ItemsSource ={Binding Source = {StaticResource Employee}}
 DisplayMemberPath =FirstName
 SelectedValue ={Binding Path = EmployeeID}
 SelectedValuePath =EmployeeID
 /> 
  

并在我的ViewModel中创建此方法以获取Employees列表;

  public IEnumerable< DataObjects.Employee> GetEmp（）
 {
 return context.Employees; 
} 
  

I have three tables. Employee, ClientEmp and Client.

ClientEmp has the ForeignKey of both Employee (EmployeeID) and Client(ClientID).

So far, I am able to save changes to ClientEmp in my database (using EF) based on the selected Client. But I have to type in the EmployeeID ForeignKey manually in a textbox to be able to match the data for it to save.

Obviously, this isn't very user friendly if a user has no idea what the EmployeeID FK is enter into the textbox either.

Therefore, is there a way to show a list of Employee Firstname's using a combo box from the Employee table and then save it to the database?

I have tried this, but it doesn't seem to work.

<ComboBox Grid.Column="1" Grid.Row="1" Name="cbEmployeeName" 
          ItemsSource="{Binding Source={StaticResource Employee}}" 
          DisplayMemberPath="FirstName" 
          SelectedValuePath="EmployeeID">
</ComboBox>

I have also tried to use This link and This link here to help but with no avail. What am I doing wrong?

Any help would be much appreciated :).

解决方案

In the end, I managed to figure it out with help from the WPF Chat room and help from Maverik.

Within my xaml I defined the following;

<ResourceDictionary>
        <ObjectDataProvider x:Key="Employee"
                            ObjectType="{x:Type vm:ClientBookKeepingViewModel}"
                            MethodName="GetEmp">
        </ObjectDataProvider>
</ResourceDictionary>

<ComboBox Grid.Column="1" Grid.Row="1" Name="cbEmployeeName" 
             ItemsSource="{Binding Source={StaticResource Employee}}" 
             DisplayMemberPath="FirstName" 
             SelectedValue="{Binding Path=EmployeeID}"
             SelectedValuePath="EmployeeID"
/>

and within my ViewModel, created this method to get a list of Employees;

public IEnumerable<DataObjects.Employee> GetEmp() 
{
    return context.Employees;
}

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