[Silverlight入门系列]使用MVVM模式(3)：Model的INotifyPropertyChanged接口实现
ObservableCollection自动实现（见上一篇））
一个简单的例子：（下面的例子中TextBlock绑定了DataContext的ModelName，点击按钮以后model更新，TextBlock会自动更新）
Model：
1 public class MyModel : INotifyPropertyChanged 2 { 3 public event PropertyChangedEventHandler PropertyChanged; 4 5 public int ModelID { get; set; } 6 7 private string _ModelName; 8 public string ModelName 9 {10 get { return _ModelName; }11 set12 {13 _ModelName = value; 14 15 if (PropertyChanged != null)16 {17 PropertyChanged(this, new PropertyChangedEventArgs("ModelName"));18 }19 }20 }21 }?
Silverlight页面：
1 <Grid x:Name="LayoutRoot" Background="White">2 <TextBlock Height="46" HorizontalAlignment="Left" Margin="187,51,0,0" Name="textBlock1" Text="{Binding ModelName}" VerticalAlignment="Top" Width="94" />3 <Button Content="update" Height="39" HorizontalAlignment="Left" Margin="187,120,0,0" Name="button1" VerticalAlignment="Top" Width="106" Click="button1_Click" />4 </Grid>?
页面代码：
1 public MyView() 2 { 3 InitializeComponent(); 4 5 MyModel m1 = new MyModel() { ModelID = 1, ModelName = "abc" }; 6 7 this.DataContext = m1; 8 } 9 10 private void button1_Click(object sender, RoutedEventArgs e)11 {12 (this.DataContext as MyModel).ModelName = "abc_changed";13 }甚至还有一个VS2010插件来完成这个工作：NotifyPropertyWeaver
ViewModel也可以实现INotifyPropertyChanged接口，很简单：
XAML绑定集合：
1 <DataGrid ItemsSource="{Binding Path=LineItems}" />?
ViewModel代码：
1 public class OrderViewModel : INotifyPropertyChanged 2 { 3 public OrderViewModel( IOrderService orderService ) 4 { 5 this.LineItems = new ObservableCollection<OrderLineItem>( 6 orderService.GetLineItemList() ); 7 } 8 9 public ObservableCollection<OrderLineItem> LineItems { get; private set; }10 }