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WPF文本框拦截路由命令

routed-commands undo keyboard-shortcuts wpf

Joseph Sturtevant · 技术社区 · 15 年前

Command Pattern TextBox

文本框 如果可能的话,在我的申请中。

<Window x:Class="InputBindingSample.Window1"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:loc="clr-namespace:InputBindingSample"
    Title="Window1" Height="300" Width="300">
    <Window.CommandBindings>
        <CommandBinding Command="loc:Window1.MyUndo" Executed="MyUndo_Executed" />
    </Window.CommandBindings>
    <DockPanel LastChildFill="True">
        <StackPanel>
            <Button Content="Ctrl+Z Works If Focus Is Here" />
            <TextBox Text="Ctrl+Z Doesn't Work If Focus Is Here" />
        </StackPanel>
    </DockPanel>
</Window>

using System.Windows;
using System.Windows.Input;

namespace InputBindingSample
{
    public partial class Window1
    {
        public static readonly RoutedUICommand MyUndo = new RoutedUICommand("MyUndo", "MyUndo", typeof(Window1),
            new InputGestureCollection(new[] { new KeyGesture(Key.Z, ModifierKeys.Control) }));

        public Window1() { InitializeComponent(); }

        private void MyUndo_Executed(object sender, ExecutedRoutedEventArgs e) { MessageBox.Show("MyUndo!"); }
    }
}

6 回复 | 直到 7 年前

stakx - no longer contributing Saravana Kumar 13 年前

没有直接的方法来抑制所有绑定,不要设置 IsUndoEnabled 到 false 因为它只会捕获和冲洗 Ctrl键 + 键绑定。你需要重定向 CanUndo CanRedo , Undo 和 Redo . 下面是我如何用我的 UndoServiceActions 辛格尔顿。

textBox.CommandBindings.Add(new CommandBinding(ApplicationCommands.Undo,
                                               UndoCommand, CanUndoCommand));
textBox.CommandBindings.Add(new CommandBinding(ApplicationCommands.Redo,
                                               RedoCommand, CanRedoCommand));

private void CanRedoCommand(object sender, CanExecuteRoutedEventArgs e)
{
    e.CanExecute = UndoServiceActions.obj.UndoService.CanRedo;
    e.Handled = true;
}

private void CanUndoCommand(object sender, CanExecuteRoutedEventArgs e)
{
    e.CanExecute = UndoServiceActions.obj.UndoService.CanUndo;
    e.Handled = true;
}

private void RedoCommand(object sender, ExecutedRoutedEventArgs e)
{
    UndoServiceActions.obj.UndoService.Redo();
    e.Handled = true;
}

private void UndoCommand(object sender, ExecutedRoutedEventArgs e)
{
    UndoServiceActions.obj.UndoService.Undo();
    e.Handled = true;
}

MRoc 14 年前

如果要实现自己的撤消/重做并防止文本框拦截,请通过附加到命令预览事件 CommandManager.AddPreviewCanExecuteHandler 和 CommandManager.AddPreviewExecutedHandler 并将event.Handled标志设置为true:

MySomething()
{
    CommandManager.AddPreviewCanExecuteHandler(
        this,
        new CanExecuteRoutedEventHandler(OnPreviewCanExecuteHandler));
    CommandManager.AddPreviewExecutedHandler(
        this,
        new ExecutedRoutedEventHandler(OnPreviewExecutedEvent));
}
void OnPreviewCanExecuteHandler(object sender, CanExecuteRoutedEventArgs e)
{
    if (e.Command == ApplicationCommands.Undo)
    {
        e.CanExecute = true;
        e.Handled = true;
    }
    else if (e.Command == ApplicationCommands.Redo)
    {
        e.CanExecute = true;
        e.Handled = true;
    }
}
void OnPreviewExecutedEvent(object sender, ExecutedRoutedEventArgs e)
{
    if (e.Command == ApplicationCommands.Undo)
    {
        // DO YOUR UNDO HERE
        e.Handled = true;
    }
    else if (e.Command == ApplicationCommands.Redo)
    {
        // DO YOUR REDO HERE
        e.Handled = true;
    }
}

AndyM 15 年前

默认情况下,目标 RoutedUICommand CommandTarget 在发出命令的控件上,以更改接收命令的根元素。

<MenuItem Command="ApplicationCommands.Open"
          CommandTarget="{Binding ElementName=UIRoot}"
          Header="_Open" />

Mark Synowiec 15 年前

执行的事件会出现气泡,因此窗口执行的事件将始终在TextBox执行的事件之后命中。尝试将其更改为PreviewExecuted,它将产生巨大的变化。此外,您可能还需要为您的窗口连接CanExecute。即:

<CommandBinding Command="Undo" PreviewExecuted="MyUndo_Executed" CanExecute="SomeOtherFunction"/>

private void SomeOtherFunction(object sender, ExecutedRoutedEventArgs e) { e.CanExecute=true; }

当然,您可能需要一些逻辑来确定何时将CanExecute设置为true。您可能也不需要使用自定义命令(只需使用内置的Undo)。

Pavel Minaev 15 年前

TextBoxBase TextBox 和 RichTextBox )有 IsUndoEnabled 属性,默认为 true false (和往常一样,您可以通过样式和setter对窗口上的所有文本框执行事件设置),这样它们就不会拦截Ctrl+Z。

Jasper wontondon 13 年前

这个 TextBox 控件提供了 IsUndoEnabled 可以设置为 false 以防止撤消功能。(如果是 true + Z

然后可以提供一个新的 CanExecute 总是响应false的事件处理程序。这里有一个

CommandBinding commandBinding = new CommandBinding(
ApplicationCommands.Cut, null, SuppressCommand);
txt.CommandBindings.Add(commandBinding);

下面是设置声明:

private void SuppressCommand(object sender, CanExecuteRoutedEventArgs e)
{
  e.CanExecute = false;
  e.Handled = true;
}