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MVVM模式是把表现层和业务层完全分离，所以这里就使用MVVM制作一个极其简单的WPF的例子：
先看看最终图：
上图，需要实现的是，界面两个按钮，一个是生成随机两个数，一个是对两个数比较，把大的数显示出来。所以需要三个属性，两个事件。
由于逻辑比较简单，不用写model等类，实现如下：
1、创建基类NotifictionObject.cs，实现接口INotifyPropertyChanged
class NotifictionObject : INotifyPropertyChanged { public event PropertyChangedEventHandler PropertyChanged; public void RaisePropertyChanged(string str) { if (this.PropertyChanged != null) this.PropertyChanged(this, new PropertyChangedEventArgs(str)); } }
2、创建DelegateCommand.cs，继承ICommand
class DelegateCommand : ICommand { public Func<object,bool> CanExecuteFunc { get; set; } public Action<object> ExecuteAction { get; set; } public event EventHandler CanExecuteChanged; public bool CanExecute(object parameter) { if (CanExecuteFunc == null) return true; return CanExecuteFunc(parameter); } public void Execute(object parameter) { if (ExecuteAction == null) return; ExecuteAction(parameter); } }
3、再创建类MainWindowViewModel.cs，继承NotifictionObject基类
class MainWindowViewModel : NotifictionObject { private int a; public int RndA { get { return a; } set { a = value; RaisePropertyChanged("RndA"); } } private int b; public int RndB { get { return b; } set { b = value; RaisePropertyChanged("RndB"); } } private int result; public int Result { get { return result; } set { result = value; RaisePropertyChanged("Result"); } } public DelegateCommand CompareCommand { get; set; } public DelegateCommand ReNewRndNumCommand { get; set; } Random rnd = new Random(); public MainWindowViewModel() { LoadData(); CompareCommand = new DelegateCommand(); CompareCommand.ExecuteAction = (para) => { Result = RndA >= RndB ? RndA : RndB; }; ReNewRndNumCommand = new DelegateCommand(); ReNewRndNumCommand.ExecuteAction = (para) => { LoadData(); }; } public void LoadData() { RndA = rnd.Next(0, 100); RndB = rnd.Next(0, 100); } }
4、类都实现了，现在实现界面部分
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<TextBlock Margin="10" x:Name="textBlock" TextWrapping="Wrap" Text="数字1:"/>
<TextBlock Margin="10" x:Name="textBlock1" Grid.Column="1" TextWrapping="Wrap" Text="{Binding RndA}"/>
<TextBlock Margin="10" x:Name="textBlock2" Grid.Column="2" TextWrapping="Wrap" Text="数字2:"/>
<TextBlock Margin="10" x:Name="textBlock3" Grid.Column="3" TextWrapping="Wrap" Text="{Binding RndB}"/>
<Button Grid.Row="1" Command="{Binding ReNewRndNumCommand}" Grid.ColumnSpan="2" Width="75" Margin="10">重新生成数</Button>
<Button x:Name="button" Command="{Binding CompareCommand}" Margin="10" Content="比较大小" Grid.ColumnSpan="2" Grid.Row="1" Grid.Column="2" Width="75"/>
<TextBlock x:Name="textBlock4" Margin="10" HorizontalAlignment="Center" Grid.Column="0" Grid.Row="2" Grid.ColumnSpan="4" TextWrapping="Wrap" Text="{Binding Result}"/>
</Grid>
5.在主界面的C#初始化时添加上下文：
public MainWindow() { InitializeComponent(); this.DataContext = new MainWindowViewModel(); }
代码就不详细介绍了，自己慢慢看，不是太难，多多练习。
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原文地址：http://www.cnblogs.com/lunawzh/p/4803075.html
