利用DataGrid控件实现联动的功能,在数据库客户软件中是随处可见的,然而网上的资料却是少之又少,令人崩溃。
本篇博文将介绍利用DataGrid控件模板定义的三个ComboBox实现“省、市、区”的三级联动。步骤如下:
一.定义地域信息类(注意包含System.ComponentModel命名空间)
- class RegionInfo : INotifyPropertyChanged //地区信息
- {
- private string _province;//省
- private string _city;//市
- private string _area;//区
- public event PropertyChangedEventHandler PropertyChanged;
- public string Province
- {
- get { return _province; }
- set
- {
- _province = value;
- PropertyChanged(this, new PropertyChangedEventArgs("Province"));
- }
- }
- public string City
- {
- get { return _city; }
- set
- {
- _city = value;
- PropertyChanged(this, new PropertyChangedEventArgs("City"));
- }
- }
- public string Area
- {
- get { return _area; }
- set
- {
- _area = value;
- PropertyChanged(this, new PropertyChangedEventArgs("Area"));
- }
- }
- public RegionInfo(string province, string city, string area)//构造函数
- {
- _province = province;
- _city = city;
- _area = area;
- }
- }
二.编写DataGrid控件的XAML代码
- <!--AutoGenerateColumns="False"这句话告诉控件不自动生成列,是必要的,如果没有,控件会更具数据源自动生成列,这个在我们这种写法中看起来就有重复的两列数据-->
- <DataGrid x:Name="dataGrid" ItemsSource="{Binding}" AutoGenerateColumns="False" HorizontalAlignment="Left" VerticalAlignment="Top" Height="319" Width="302">
- <DataGrid.Columns>
- <!--省-->
- <DataGridTemplateColumn Header="省" Width="100">
- <!--显示模式-->
- <DataGridTemplateColumn.CellTemplate>
- <DataTemplate>
- <TextBlock Text="{Binding Path=Province ,Mode=TwoWay}"></TextBlock>
- </DataTemplate>
- </DataGridTemplateColumn.CellTemplate>
- <!--编辑模式-->
- <DataGridTemplateColumn.CellEditingTemplate>
- <DataTemplate>
- <ComboBox x:Name="ComboBoxProvince" DropDownClosed="ProvinceDropDownClosed" Loaded="ProvinceLoaded" Text="{Binding Path=Province ,Mode=TwoWay}" DisplayMemberPath="Province" ></ComboBox>
- </DataTemplate>
- </DataGridTemplateColumn.CellEditingTemplate>
- </DataGridTemplateColumn>
- <!--市-->
- <DataGridTemplateColumn Header="市" Width="100">
- <!--显示模式-->
- <DataGridTemplateColumn.CellTemplate>
- <DataTemplate>
- <TextBlock Text="{Binding Path=City ,Mode=TwoWay}"></TextBlock>
- </DataTemplate>
- </DataGridTemplateColumn.CellTemplate>
- <!--编辑模式-->
- <DataGridTemplateColumn.CellEditingTemplate>
- <DataTemplate>
- <ComboBox x:Name="ComboBoxCity" DropDownClosed="CityDropDownClosed" Loaded="CityLoaded" Text="{Binding Path=City,Mode=TwoWay}" DisplayMemberPath="City" ></ComboBox>
- </DataTemplate>
- </DataGridTemplateColumn.CellEditingTemplate>
- </DataGridTemplateColumn>
- <!--区-->
- <DataGridTemplateColumn Header="区" Width="100">
- <!--显示模式-->
- <DataGridTemplateColumn.CellTemplate>
- <DataTemplate>
- <TextBlock Text="{Binding Path=Area}"></TextBlock>
- </DataTemplate>
- </DataGridTemplateColumn.CellTemplate>
- <!--编辑模式-->
- <DataGridTemplateColumn.CellEditingTemplate>
- <DataTemplate>
- <ComboBox x:Name="ComboBoxArea" DropDownClosed="AreaDropDownClosed" Loaded="AreaLoaded" Text="{Binding Path=Area}" DisplayMemberPath="Area" ></ComboBox>
- </DataTemplate>
- </DataGridTemplateColumn.CellEditingTemplate>
- </DataGridTemplateColumn>
- </DataGrid.Columns>
- </DataGrid>
三.为DataGrid控件准备数据源对象
对象声明
- ObservableCollection<RegionInfo> regionInfoList = new ObservableCollection<RegionInfo>();//DataGrid的数据源
对象添加
- //DataGrid初始绑定数据
- regionInfoList.Add(new RegionInfo("广东省", "深圳市", "罗湖区"));
- regionInfoList.Add(new RegionInfo("广东省", "深圳市", "南山区"));
对象绑定
- dataGrid.ItemsSource = regionInfoList;//绑定数据源
四.为DataGrid控件的模板列加载时提供选项
对象声明
- ObservableCollection<RegionInfo> regionInfoSelectList = new ObservableCollection<RegionInfo>();//用于DataGrid的模板列加载时提供选项
对象添加
- //三级联动数据项
- regionInfoSelectList.Add(new RegionInfo("广东省", "深圳市", "罗湖区"));
- regionInfoSelectList.Add(new RegionInfo("广东省", "深圳市", "南山区"));
- regionInfoSelectList.Add(new RegionInfo("广东省", "潮州市", "湘桥区"));
- regionInfoSelectList.Add(new RegionInfo("广东省", "潮州市", "枫溪区"));
- regionInfoSelectList.Add(new RegionInfo("湖北省", "武汉市", "江夏区"));
- regionInfoSelectList.Add(new RegionInfo("湖北省", "武汉市", "武昌区"));
五.在DataGrid模板列加载的时候实时更新其数据源并绑定到ComboBox的选项中
- /// <summary>
- /// ProvinceLoaded 省份下拉列表框初始化,绑定数据源
- /// </summary>
- void ProvinceLoaded(object sender, RoutedEventArgs e)
- {
- ComboBox curComboBox = sender as ComboBox;
- //为下拉控件绑定数据源,并选择原选项为默认选项
- string text = curComboBox.Text;
- //去除重复项查找,跟数据库连接时可以让数据库来实现
- var query = regionInfoSelectList.GroupBy(p => p.Province).Select(p => new { Province = p.FirstOrDefault().Province });
- int itemcount = 0;
- curComboBox.SelectedIndex = itemcount;
- foreach (var item in query.ToList())
- {
- if (item.Province == text)
- {
- curComboBox.SelectedIndex = itemcount;
- break;
- }
- itemcount++;
- }
- curComboBox.ItemsSource = query;
- curComboBox.IsDropDownOpen = true;//获得焦点后下拉
- }
- /// <summary>
- /// CityLoaded 市下拉列表框初始化,绑定数据源
- /// </summary>
- void CityLoaded(object sender, RoutedEventArgs e)
- {
- //获得当前选中项的省份信息
- string province = (dataGrid.SelectedItem as RegionInfo).Province;
- //查找选中省份下的市作为数据源
- var query = (from l in regionInfoSelectList
- where (l.Province == province)
- group l by l.City into grouped
- select new { City = grouped.Key });
- ComboBox curComboBox = sender as ComboBox;
- //为下拉控件绑定数据源,并选择原选项为默认选项
- string text = curComboBox.Text;
- //去除重复项查找,跟数据库连接时可以让数据库来实现
- int itemcount = 0;
- curComboBox.SelectedIndex = itemcount;
- foreach (var item in query.ToList())
- {
- if (item.City == text)
- {
- curComboBox.SelectedIndex = itemcount;
- break;
- }
- itemcount++;
- }
- curComboBox.ItemsSource = query;
- curComboBox.IsDropDownOpen = true;//获得焦点后下拉
- }
- /// <summary>
- /// AreaLoaded 区下拉列表框初始化,绑定数据源
- /// </summary>
- void AreaLoaded(object sender, RoutedEventArgs e)
- {
- string province = (dataGrid.SelectedItem as RegionInfo).Province;
- string city = (dataGrid.SelectedItem as RegionInfo).City;
- //查找选中省份下的市作为数据源
- var query = (from l in regionInfoSelectList
- where (l.Province == province && l.City == city)
- group l by l.Area into grouped
- select new { Area = grouped.Key });
- ComboBox curComboBox = sender as ComboBox;
- //为下拉控件绑定数据源,并选择原选项为默认选项
- string text = curComboBox.Text;
- //去除重复项查找,跟数据库连接时可以让数据库来实现
- int itemcount = 0;
- curComboBox.SelectedIndex = itemcount;
- foreach (var item in query.ToList())
- {
- if (item.Area == text)
- {
- curComboBox.SelectedIndex = itemcount;
- break;
- }
- itemcount++;
- }
- curComboBox.ItemsSource = query;
- curComboBox.IsDropDownOpen = true;//获得焦点后下拉
- }
做到这一步基本上算是做完了,但是编译运行后会发现在选择省或者市的时候,后面的选项并没有做相应的改变,这是上一篇文章 C# WPF DataGrid控件同行编辑的实时更新问题 所述的问题,所以还需最后一步
六.参考 C# WPF DataGrid控件同行编辑的实时更新问题 解决更新问题(懒得再写一遍了哈哈)
哦哦,更新代码分别写在
- /// <summary>
- /// CityDropDownClosed 市下拉列表框选择改变刷新
- /// </summary>
- private void CityDropDownClosed(object sender, EventArgs e)
- {
- }
- /// <summary>
- /// ProvinceDropDownClosed 省份下拉列表框选择改变刷新
- /// </summary>
- private void ProvinceDropDownClosed(object sender, EventArgs e)
- {
- }
- /// <summary>
- /// AreaDropDownClosed 区下拉列表框选择改变刷新
- /// </summary>
- private void AreaDropDownClosed(object sender, EventArgs e)
- {
- }
这三个函数中。如果还想再只能点,在省下拉列表选择后,市下拉列表下拉。市下拉列表选择后,区下拉列表下拉,则可以参考 C# WPF 模拟键盘输入与UI控件进行交互 这篇文章,然后在上面提到的省、市两个下拉列表框中模拟键盘按下“TAD”键即可。