/// <summary>/// 声明并定义命令。/// </summary>RoutedCommand ClearCommand = new RoutedCommand("Clear", typeof(MainWindow));/// <summary>/// 初始化命令。崔有来 2014-7-30 06:23:10/// </summary>void InitializeCommand(){    // 为命令设置快捷键。    this.ClearCommand.InputGestures.Add(new KeyGesture(Key.C, ModifierKeys.Alt));    // 将命令赋给命令源。    this.Button1.Command = this.ClearCommand;    // 指定命令目标。    this.Button1.CommandTarget = this.TextBoxA;    // 创建命令关联并安置在外围控件上。    CommandBinding cb = new CommandBinding();    cb.Command = this.ClearCommand;    cb.CanExecute += new CanExecuteRoutedEventHandler(cb_CanExecute);    cb.Executed += new ExecutedRoutedEventHandler(cb_Executed);    this.StackPanel1.CommandBindings.Add(cb);}/// <summary>/// 当命令送达目标后执行该方法。崔有来 2014-7-30 06:27:16/// </summary>/// <param name="sender"></param>/// <param name="e"></param>void cb_Executed(object sender, ExecutedRoutedEventArgs e){    this.TextBoxA.Clear();    e.Handled = true;}/// <summary>/// 当探测命令是否可执行时调用该方法。崔有来 2014-7-30 06:26:20/// </summary>/// <param name="sender"></param>/// <param name="e"></param>void cb_CanExecute(object sender, CanExecuteRoutedEventArgs e){    if (string.IsNullOrEmpty(this.TextBoxA.Text) == true) e.CanExecute = false;    else e.CanExecute = true;    e.Handled = true;}