<Window x:Class="CommandApplication.MainWindow"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"xmlns:local="clr-namespace:CommandApplication"mc:Ignorable="d"Title="MainWindow" Height="175" Width="200"><StackPanel x:Name="stackPanel"><Button x:Name="button1" Content="Send Command" Margin="5"/><TextBox x:Name="textBoxA" Margin="5,0" Height="100"/></StackPanel>
</Window>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;namespace CommandApplication
{/// <summary>/// Interaction logic for MainWindow.xaml/// </summary>public partial class MainWindow : Window{public MainWindow(){InitializeComponent();InitializeCommand();}//RoutedCommand 是系统自带常用的命令类 //申明命令实例private RoutedCommand clearCmd = new RoutedCommand("Clear", typeof(MainWindow));private void InitializeCommand(){//指定命令源this.button1.Command = this.clearCmd;this.clearCmd.InputGestures.Add(new KeyGesture(Key.C, ModifierKeys.Alt));//指定命令目标，命令源属性中指定sthis.button1.CommandTarget = this.textBoxA;//创建命令关联CommandBinding cb = new CommandBinding();cb.Command = this.clearCmd;cb.CanExecute += new CanExecuteRoutedEventHandler(cb_CanExecute);cb.Executed += new ExecutedRoutedEventHandler(cb_Execute);//this.stackPanel.CommandBindings.Add(cb);this.textBoxA.CommandBindings.Add(cb);}//当命令送达目标后，此方法被调用private void cb_Execute(object sender, ExecutedRoutedEventArgs e){this.textBoxA.Clear();e.Handled = true;}//当探测命令是否可执行时，此方法被调用private void cb_CanExecute(object sender, CanExecuteRoutedEventArgs e){if (string.IsNullOrEmpty(this.textBoxA.Text)){ e.CanExecute = false; }else{ e.CanExecute = true; }e.Handled = true;}}
}