public class MainModel:INotifyPropertyChanged{public event PropertyChangedEventHandler PropertyChanged;private void INotifyPropertyChanged(string name){if (PropertyChanged != null){PropertyChanged(this, new PropertyChangedEventArgs(name));}}private int xh;public int Xh{get { return xh; }set { xh = value; }}private string name;public string Name{get { return name; }set { name = value;INotifyPropertyChanged("Name");}}private int age;public int Age{get { return age; }set { age = value;INotifyPropertyChanged("Age");}}private bool isSelected;public bool IsSelected{get { return isSelected; }set { isSelected = value;INotifyPropertyChanged("IsSelected");}}}

public class MainViewModel : ViewModelBase{public MainViewModel(){DataGridBaseInfo = AddDataGridInfo();}/// <summary>/// 给Datagrid绑定的属性/// </summary>private List<MainModel> dataGridBaseInfo;public List<MainModel> DataGridBaseInfo{get { return dataGridBaseInfo; }set{dataGridBaseInfo = value;RaisePropertyChanged("DataGridBaseInfo");}}/// <summary>/// 显示按钮/// </summary>private RelayCommand buttonCommand;public RelayCommand ButtonCommand{get{return buttonCommand ?? (buttonCommand = new RelayCommand(() =>{int count = DataGridBaseInfo.ToList().FindAll(p => p.IsSelected == true).Count;MessageBox.Show("选中了" + count + "项");//for (int i = 0; i < count; i++)//    MessageBox.Show(DataGridBaseInfo.ToList().FindAll(p=>p.IsSelected==true)[i].Name + "," + DataGridBaseInfo.ToList().FindAll(p=>p.IsSelected==true)[i].Age);
                    }));}            }public List<MainModel> AddDataGridInfo(){MainModel model;List<MainModel> list = new List<MainModel>();for (int i = 0; i < 5; i++){model = new MainModel();model.Xh = i;model.Name = "李雷" + i;model.Age = 20 + i;list.Add(model);}return list;}/// <summary>/// 选中/// </summary>private RelayCommand selectCommand;public RelayCommand SelectCommand{get{return selectCommand ?? (selectCommand = new RelayCommand(() =>{int selectCount = DataGridBaseInfo.ToList().Count(p => p.IsSelected == false);if (selectCount.Equals(0)){IsSelectAll = true;}}));}}/// <summary>/// 取消选中/// </summary>private RelayCommand unSelectCommand;public RelayCommand UnSelectCommand{get{return unSelectCommand ?? (unSelectCommand = new RelayCommand(() =>{IsSelectAll = false;}));}}private bool isSelectAll = false;public bool IsSelectAll{get { return isSelectAll; }set{isSelectAll = value;RaisePropertyChanged("IsSelectAll");}}/// <summary>/// 选中全部/// </summary>private RelayCommand selectAllCommand;public RelayCommand SelectAllCommand{get{return selectAllCommand ?? (selectAllCommand = new RelayCommand(ExecuteSelectAllCommand, CanExecuteSelectAllCommand));}}private void ExecuteSelectAllCommand(){if (DataGridBaseInfo.Count < 1) return;DataGridBaseInfo.ToList().FindAll(p => p.IsSelected = true);}private bool CanExecuteSelectAllCommand(){if (DataGridBaseInfo != null){return DataGridBaseInfo.Count > 0;}elsereturn false;}/// <summary>/// 取消全部选中/// </summary>private RelayCommand unSelectAllCommand;public RelayCommand UnSelectAllCommand{get { return unSelectAllCommand ?? (unSelectAllCommand = new RelayCommand(ExecuteUnSelectAllCommand, CanExecuteUnSelectAllCommand)); }}private void ExecuteUnSelectAllCommand(){if (DataGridBaseInfo.Count < 1)return;if (DataGridBaseInfo.ToList().FindAll(p => p.IsSelected == false).Count != 0)IsSelectAll = false;elseDataGridBaseInfo.ToList().FindAll(p => p.IsSelected = false);}private bool CanExecuteUnSelectAllCommand(){if (DataGridBaseInfo != null){return DataGridBaseInfo.Count > 0;}else{return false;}}}

<Grid><Grid.RowDefinitions><RowDefinition Height="20"/><RowDefinition Height="*"/><RowDefinition Height="20"/></Grid.RowDefinitions><DataGrid Grid.Row="1" ItemsSource="{Binding DataGridBaseInfo, Mode=TwoWay}" Margin="10" AutoGenerateColumns="False"><DataGrid.Columns>                <DataGridTemplateColumn><DataGridTemplateColumn.Header><CheckBox Content="全选" IsChecked="{Binding IsSelectAll,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"><i:Interaction.Triggers>                                <i:EventTrigger EventName="Checked"><Custom:EventToCommand Command="{Binding DataContext.SelectAllCommand, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}" CommandParameter="{Binding IsSelectAll, ElementName=qx}"/></i:EventTrigger><i:EventTrigger EventName="Unchecked"><Custom:EventToCommand Command="{Binding DataContext.UnSelectAllCommand,  RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}" CommandParameter="{Binding IsSelectAll, ElementName=qx}"/></i:EventTrigger>                                </i:Interaction.Triggers></CheckBox></DataGridTemplateColumn.Header><DataGridTemplateColumn.CellTemplate>                        <DataTemplate><StackPanel Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center"><CheckBox x:Name="cbXh"  VerticalAlignment="Center" IsChecked="{Binding IsSelected, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"><i:Interaction.Triggers><i:EventTrigger EventName="Checked"><Custom:EventToCommand Command="{Binding DataContext.SelectCommand, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}" CommandParameter="{Binding IsChecked, ElementName=cbXh}"/></i:EventTrigger><i:EventTrigger EventName="Unchecked"><Custom:EventToCommand Command="{Binding DataContext.UnSelectCommand,  RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}" CommandParameter="{Binding IsChecked, ElementName=cbXh}"/></i:EventTrigger></i:Interaction.Triggers></CheckBox><Label Content="{Binding Xh}" FontSize="14"/></StackPanel></DataTemplate></DataGridTemplateColumn.CellTemplate></DataGridTemplateColumn>                <DataGridTextColumn Header="姓名" Binding="{Binding Name}" Width="*"/><DataGridTextColumn Header="年龄" Binding="{Binding Age}" Width="*"/></DataGrid.Columns>            </DataGrid><Button Content="显示" Grid.Row="2" Width="50" Command="{Binding ButtonCommand}"/></Grid>