我在WPF应用程序中使用EntityFramework库,我遇到以下问题: 我正在使用MVVM模式(据我所知),我正在尝试使用EF值进行Combobox查找。
这是OfficeView类:
public partial class AddOffice : Window
{
private DBHelper.ResourceManagementContext context = new DBHelper.ResourceManagementContext();
public AddOffice()
{
InitializeComponent();
context.Companies.Load();
this.DataContext = context.Companies.Local;
//this.DataContext = new AddOfficeViewModel();
}
public void CloseCommandHandler(object sender, ExecutedRoutedEventArgs e)
{
this.Close();
}
}
这是相应的XAML:
<Label Grid.Row="4" Grid.Column="0" Margin="10,10">Company:</Label>
<ComboBox Grid.Row="4" Grid.Column="1" Margin="10,10"
ItemsSource="{Binding}"
DisplayMemberPath="CompanyName"
SelectedValuePath="CompanyName"
SelectedValue="{Binding Path=CompanyName}"/>
我知道MVVM模式通常会将ViewModel传递给View,那么我如何使用OfficeViewModel将EntityFramework Company列表绑定到ComboBox?
我理解ComboBox属性。我知道所选的值将是Office对象中的CompanyName,而SeletecValuePath将是Company对象中的CompanyName。
答案 0 :(得分:4)
在视图模型中:
class OfficeViewModel
{
private string _CompanyName;
public string CompanyName
{
get
{
return _CompanyName;
}
set
{
_CompanyName = value;
NotifyPropertyChanged("CompanyName");
}
}
private List<Location> _CompanyList;
public List<Location> CompanyList
{
get
{
return _CompanyList;
}
set
{
_CompanyList = value;
NotifyPropertyChanged("CompanyList");
}
}
public List<Company> GetCompanyList()
{
return (from comp in Entity.Companies select comp).ToList();
}
}
在Xaml中:
在xaml中添加名称空间,如下所示:
xmlns:ViewModels="clr-namespace:WpfMvvmApplication.ViewModels"
在window.resources中添加以下内容:
<Window.Resources>
<ViewModels:OfficeViewModel x:Key="OfficeController"/>
</Window.Resources>
将视图模型绑定到组合框:
<Label Grid.Row="4" Grid.Column="0" Margin="10,10">Company:</Label>
<ComboBox Grid.Row="4" Grid.Column="1" Margin="10,10"
ItemsSource="{Binding CompanyList, Source={StaticResource OfficeController}}"
DisplayMemberPath="CompanyName"
SelectedValuePath="CompanyName"
SelectedValue="{Binding Path=CompanyName}"/>
希望这会对你有所帮助。