WPF - 路由命令

路由命令以更語義化的級別啟用輸入處理。這些實際上是簡單的指令，如新建、開啟、複製、剪下和儲存。這些命令非常有用，可以從選單或鍵盤快捷鍵中訪問它們。如果命令變為不可用，它將停用控制元件。以下示例定義選單項的命令。

• 讓我們建立一個名為WPFCommandsInput的新 WPF 專案。

• 將選單控制元件拖動到堆疊面板，然後設定以下屬性和命令，如在以下 XAML 檔案中所示。

<Window x:Class = "WPFContextMenu.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:WPFContextMenu" 
   mc:Ignorable = "d" Title = "MainWindow" Height = "350" Width = "525">
	
   <Grid> 
      <StackPanel x:Name = "stack" Background = "Transparent"> 
		
         <StackPanel.ContextMenu> 
            <ContextMenu> 
               <MenuItem Header = "New" Command = "New" /> 
               <MenuItem Header = "Open" Command = "Open" /> 
               <MenuItem Header = "Save" Command = "Save" /> 
            </ContextMenu> 
         </StackPanel.ContextMenu>
			
         <Menu> 
            <MenuItem Header = "File" > 
               <MenuItem Header = "New" Command = "New" /> 
               <MenuItem Header = "Open" Command = "Open" /> 
               <MenuItem Header = "Save" Command = "Save" /> 
            </MenuItem> 
         </Menu> 
			
      </StackPanel> 
   </Grid> 
	
</Window> 

以下是處理不同命令的 C# 程式碼。

using System.Windows; 
using System.Windows.Input; 
 
namespace WPFContextMenu { 
   /// <summary> 
      /// Interaction logic for MainWindow.xaml 
   /// </summary> 
	
   public partial class MainWindow : Window { 
	
      public MainWindow() { 
         InitializeComponent(); 
         CommandBindings.Add(new CommandBinding(ApplicationCommands.New, NewExecuted, CanNew)); 
         CommandBindings.Add(new CommandBinding(ApplicationCommands.Open, OpenExecuted, CanOpen)); 
         CommandBindings.Add(new CommandBinding(ApplicationCommands.Save, SaveExecuted, CanSave)); 
      } 
		
      private void NewExecuted(object sender, ExecutedRoutedEventArgs e) { 
         MessageBox.Show("You want to create new file."); 
      }  
		
      private void CanNew(object sender, CanExecuteRoutedEventArgs e) { 
         e.CanExecute = true; 
      } 
		
      private void OpenExecuted(object sender, ExecutedRoutedEventArgs e) { 
         MessageBox.Show("You want to open existing file."); 
      }  
		
      private void CanOpen(object sender, CanExecuteRoutedEventArgs e) { 
         e.CanExecute = true; 
      } 
		
      private void SaveExecuted(object sender, ExecutedRoutedEventArgs e) { 
         MessageBox.Show("You want to save a file."); 
      } 
      private void CanSave(object sender, CanExecuteRoutedEventArgs e) { 
         e.CanExecute = true; 
      } 
   } 
	
}	

編譯並執行以上程式碼後，將生成以下視窗 −

現在，你可以從選單或快捷鍵命令訪問這些選單項。從任一選項中，它將執行命令。