双向比例在WPF格式化绑定 [英] Two way percentage formatted binding in WPF

问题描述

我有这样的文本框：

<TextBox Text="{Binding Path=TaxFactor, StringFormat=P}" />

它正确地显示 0.05 为 5％，但它不工作，回去。当我输入一个百分比，它失败，因为百分比符号。如果我试着写只是一个数字，如 5 ，我得到 500％代替。我要写 0.05 为它工作。

It correctly displays 0.05 as 5%, but it doesn't work going back. When I type in a percentage, it fails because of the percent symbol. If I try writing just a number, like 5, I get 500% instead. I have to write 0.05 for it to work.

我必须写一个自定义转换，让我的百分比回来？如果是这样，我怎么周围设置特定百分比的格式得到什么呢？

Do I have to write a custom converter to get my percentage back? And if so, how do I get around locale-specific percentage formats?

推荐答案

您需要编写一个自定义的转换器。注意：这一个假设值存储在范围为0〜100，而不是0到1

You need to write a custom converter. NOTE: this one assumes that the values are stored in the range 0 to 100 rather than 0 to 1.

public object Convert(object value, Type targetType, object parameter,
                      System.Globalization.CultureInfo culture)
{
    if (string.IsNullOrEmpty(value.ToString())) return 0;

    if (value.GetType() == typeof(double)) return (double)value / 100;

    if (value.GetType() == typeof(decimal)) return (decimal)value / 100;    

    return value;
}

public object ConvertBack(object value, Type targetType, object parameter,
                          System.Globalization.CultureInfo culture)
{
    if (string.IsNullOrEmpty(value.ToString())) return 0;

    var trimmedValue = value.ToString().TrimEnd(new char[] { '%' });

    if (targetType == typeof(double))
    {
        double result;
        if (double.TryParse(trimmedValue, out result))
            return result;
        else
            return value;
    }

    if (targetType == typeof(decimal))
    {
        decimal result;
        if (decimal.TryParse(trimmedValue, out result))
            return result;
        else
            return value;
    }
    return value;
}

调用它是这样的：

The call it like this:

<TextBox Text="{Binding Path=TaxFactor, Mode=TwoWay, StringFormat=P, 
         Converter={StaticResource percentStringFormatConverter} />

这是一些Silverlight的code，但应与WPF 的

这篇关于双向比例在WPF格式化绑定的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！