覆盖文本框的文本属性

Question

How do I override the text property in a textbox in WPF ?

I want this code in WPF:

 public override string Text
 {
        get { return Text.Replace(",", ""); }
        set { Text = value; }
 }

Answer 1

If you are data binding against the TextBox.Text property then another possible approach is to move the logic away from the control itself and place it in a converter. Your converter would look something like this...

public class CommaReplaceConverter : IValueConverter
{
    public object Convert(object value, Type targetType, 
                          object parameter, CultureInfo culture)
    {
        return value;
    }

    public object ConvertBack(object value, Type targetType, 
                              object parameter, CultureInfo culture)
    {
        return value.ToString().Replace(",", "");
    }
}

And data binding something like this...

<TextBox Text="{Binding XXX, Converter={StaticResource CRC}" />

...where the static resource is defined as...

<Window.Resources>
    <CommaReplaceConverter x:Key="CRC"/>
</Windows.Resources>

Answer 2

Text is a dependency property. If you have derived a class from TextBox then you need to override the metadata and provide your validation callbacks

See

• http://blog.ningzhang.org/2008/11/dependencyproperty-validation-coercion.html
• http://msdn.microsoft.com/en-us/library/ms745795.aspx#Validation_Callbacks

Answer 3

虽然upvoted答案是正确的，但有一个更简单的方法：因为TextBox的Text属性绑定到底层类的属性（通常在Viewmodel中），只需要在底层类中提供替换。

Answer 4

You were just missing the text argument?

public override string Text 
    { 
        get { return Text.Replace(",", Text); } 
        set { Text = value; } 
    }