c# - 在 WPF TextBox 中禁止特殊字符 ("\/: ? "< > |") 的可重用但简单有效的方法是什么？

Question

我的应用程序中有几个 WPF 文本框，它们将用于指定文件名。我正在寻找一种解决方案，它可以快速轻松地禁止将特殊字符(即“\/: ?” < > |)输入这些文本框，而无需创建继承自 TextBox 和不需要使用正则表达式。

Answer 1

我创建了一个名为“DisallowSpecialCharatersTextBoxBehavior”的静态类，它利用了 WPF 中可附加属性的强大功能，如下所示:

public static class DisallowSpecialCharactersTextboxBehavior
{
    public static DependencyProperty DisallowSpecialCharactersProperty =
        DependencyProperty.RegisterAttached("DisallowSpecialCharacters", typeof(bool), typeof(DisallowSpecialCharactersTextboxBehavior), new PropertyMetadata(DisallowSpecialCharactersChanged));

    public static void SetDisallowSpecialCharacters(TextBox textBox, bool disallow)
    {
        textBox.SetValue(DisallowSpecialCharactersProperty, disallow);
    }

    public static bool GetDisallowSpecialCharacters(TextBox textBox)
    {
        return (bool)textBox.GetValue(DisallowSpecialCharactersProperty);
    }

    private static void DisallowSpecialCharactersChanged(DependencyObject dependencyObject, DependencyPropertyChangedEventArgs e)
    {
        var tb = dependencyObject as TextBox;
        if (tb != null)
        {

            if ((bool)e.NewValue)
            {
                tb.PreviewTextInput += tb_PreviewTextInput;
                tb.AddHandler(DataObject.PastingEvent, new DataObjectPastingEventHandler(tb_Pasting));
            }
            else
            {
                tb.PreviewTextInput -= tb_PreviewTextInput;
                tb.RemoveHandler(DataObject.PastingEvent, new DataObjectPastingEventHandler(tb_Pasting));
            }

        }
    }

    private static void tb_Pasting(object sender, DataObjectPastingEventArgs e)
    {
        var pastedText = e.DataObject.GetData(typeof(string)) as string;

        Path.GetInvalidFileNameChars().ToList().ForEach(c =>
            {
                if (pastedText.Contains(c))
                {
                    e.CancelCommand();
                }

            });
    }

    private static void tb_PreviewTextInput(object sender, System.Windows.Input.TextCompositionEventArgs e)
    {
        if (Path.GetInvalidFileNameChars().ToList().ConvertAll(x => x.ToString()).Contains(e.Text))
        {
            e.Handled = true;
        }

    }
}

它可以很容易地应用于 WPF 中的任何 TextBox，如下所示:

<Window x:Class="ExampleApp.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:local="clr-namespace:ExampleApp"
        Title="MainWindow" Height="350" Width="525">
    <Grid>
        <TextBox local:DisallowSpecialCharactersTextboxBehavior.DisallowSpecialCharacters="true"  />
    </Grid>
</Window>