Wpf ComboBox 多级正反向级联的实现

Wpf ComboBox 多级正向级联比较容易实现，想实现反向级联还是有一定难度。添加新对象只用到正向级联，而浏览不同的对象就需要用到反向级联。本示例程序为一个简约到极致的企业管理系统，使用EF Code First,Sql Compact数据库，实现不同地址的5级行政区划选择和浏览，实时产生含行政区划名称的地址。

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApp.Adress.ComboBox
{
    /// 

    /// AdressDistrict.xaml 的交互逻辑
    /// 

    public partial class AdressDistrict : UserControl
    {
        public AdressDistrict（）
        {
            InitializeComponent（）;
        }
    }
}

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     目录           0  2018-01-08 16:29  WpfApp.Adress.ComboBox\
     目录           0  2018-01-08 16:29  WpfApp.Adress.ComboBox\.vs\
     目录           0  2018-01-08 16:29  WpfApp.Adress.ComboBox\.vs\WpfApp.Adress.ComboBox\
     目录           0  2018-01-08 16:29  WpfApp.Adress.ComboBox\.vs\WpfApp.Adress.ComboBox\v15\
     文件      119296  2018-01-09 10:57  WpfApp.Adress.ComboBox\.vs\WpfApp.Adress.ComboBox\v15\.suo
     目录           0  2018-01-08 16:29  WpfApp.Adress.ComboBox\.vs\WpfApp.Adress.ComboBox\v15\Server\
     目录           0  2018-01-09 10:57  WpfApp.Adress.ComboBox\.vs\WpfApp.Adress.ComboBox\v15\Server\sqlite3\
     文件           0  2018-01-07 23:01  WpfApp.Adress.ComboBox\.vs\WpfApp.Adress.ComboBox\v15\Server\sqlite3\db.lock
     文件     1064960  2018-01-09 10:57  WpfApp.Adress.ComboBox\.vs\WpfApp.Adress.ComboBox\v15\Server\sqlite3\storage.ide
     目录           0  2018-01-09 10:48  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\
     文件        4360  2018-01-09 10:48  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\AdressDistrict.xaml
     文件         715  2018-01-08 15:28  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\AdressDistrict.xaml.cs
     文件        2060  2018-01-07 23:27  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\App.config
     文件         398  2018-01-07 23:01  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\App.xaml
     文件         349  2018-01-07 23:01  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\App.xaml.cs
     文件        2331  2018-01-08 00:25  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\BooleanToVisibilityConverter.cs
     文件        2032  2018-01-08 16:31  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\Commandbase.cs
     文件        2555  2018-01-09 09:36  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\Company.cs
     文件         619  2018-01-08 01:03  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\CompanyDbContext.cs
     文件        2581  2018-01-09 09:47  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\CompanyEditContent.xaml
     文件         697  2018-01-08 00:33  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\CompanyEditContent.xaml.cs
     文件        9279  2018-01-09 09:42  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\CompanyEditViewModel.cs
     文件        1430  2018-01-09 10:02  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\Database.cs
     文件         990  2018-01-09 10:48  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\District.cs
     文件         413  2018-01-07 23:35  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\IViewModelbase.cs
     文件        1715  2018-01-09 09:48  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\MainWindow.xaml
     文件        1201  2018-01-08 16:26  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\MainWindow.xaml.cs
     文件         790  2018-01-07 23:35  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\NotifyPropertyChanged.cs
     目录           0  2018-01-08 16:29  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\Properties\
     文件        2368  2018-01-07 23:01  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\Properties\AssemblyInfo.cs
     文件        2857  2018-01-07 23:01  WpfApp.Adress.ComboBox\WpfApp.Adress.ComboBox\Properties\Resources.Designer.cs
............此处省略158个文件信息