WPF - RoatedCommands 路由命令
RoatedCommands 可以在更语义的层面上进行输入处理。 这些实际上是简单的指令,如新建、打开、复制、剪切和保存。 这些命令非常有用,可以从菜单或键盘快捷键访问它们。 如果命令不可用,它会禁用控件。 以下示例定义了菜单项的命令。
让我们创建一个名为 WPFCommandsInput 的新 WPF 项目。
将菜单控件拖动到堆栈面板并设置以下属性和命令,如以下 XAML 文件中所示。
<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>
这是处理不同命令的 C# 代码。
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; } } }
上面的代码编译执行后,会产生如下窗口−
现在您可以通过菜单或快捷键命令访问此菜单项。 无论选择哪一个选项,它都会执行命令。