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。
