如何绑定在WPF逆布尔属性？ [英] How to bind inverse boolean properties in WPF?

问题描述

我已经是一个对象，它有一个的IsReadOnly 属性。如果此属性是真的，我想在一个按钮设置的IsEnabled 属性，（例如），为false。

我愿意相信，我可以容易地做到这一点的的IsEnabled ={绑定路径=！的IsReadOnly}但是，这并不与WPF飞。

我是降级不必经过所有的样式设置？似乎太罗嗦了一些简单为一个布尔值设置到另一个布尔逆。

 ＆LT; Button.Style＆GT;
    ＆LT;风格的TargetType ={X：类型按钮}＆GT;
        ＆LT; Style.Triggers＆GT;
            ＆LT; D​​ataTrigger绑定={绑定路径=的IsReadOnly}值=真＆GT;
                ＆LT; setter属性=IsEnabled的VALUE =FALSE/＆GT;
            ＆LT; / DataTrigger＆GT;
            ＆LT; D​​ataTrigger绑定={绑定路径=的IsReadOnly}值=FALSE＆GT;
                ＆LT; setter属性=IsEnabled的VALUE =真/＆GT;
            ＆LT; / DataTrigger＆GT;
        ＆LT; /Style.Triggers>
    ＆LT; /样式和GT;
＆LT; /Button.Style>
 

解决方案

您可以使用ValueConverter是反转一个bool属性你。

XAML：

 的IsEnabled ={绑定路径=的IsReadOnly，转换器= {的StaticResource InverseBooleanConverter}}
 

转换：

  [ValueConversion（typeof运算（布尔）的typeof（布尔））]
    公共类InverseBooleanConverter：的IValueConverter
    {
        ＃地区的IValueConverter会员

        公共对象转换（对象的值，类型TARGETTYPE，对象参数，
            System.Globalization.CultureInfo文化）
        {
            如果（TARGETTYPE！= typeof运算（布尔））
                抛出新的InvalidOperationException异常（我们的目标是布尔）;

            返回（布尔）值！;
        }

        公共对象ConvertBack（对象的值，类型TARGETTYPE，对象参数，
            System.Globalization.CultureInfo文化）
        {
            抛出新NotSupportedException异常（）;
        }

        #endregion
    }
 

What I have is an object that has an IsReadOnly property. If this property is true, I would like to set the IsEnabled property on a Button, ( for example ), to false.

I would like to believe that I can do it as easily as IsEnabled="{Binding Path=!IsReadOnly}" but that doesn't fly with WPF.

Am I relegated to having to go through all of the style settings? Just seems too wordy for something as simple as setting one bool to the inverse of another bool.

<Button.Style>
    <Style TargetType="{x:Type Button}">
        <Style.Triggers>
            <DataTrigger Binding="{Binding Path=IsReadOnly}" Value="True">
                <Setter Property="IsEnabled" Value="False" />
            </DataTrigger>
            <DataTrigger Binding="{Binding Path=IsReadOnly}" Value="False">
                <Setter Property="IsEnabled" Value="True" />
            </DataTrigger>
        </Style.Triggers>
    </Style>
</Button.Style>

解决方案

You can use a ValueConverter that inverts a bool property for you.

XAML:

IsEnabled="{Binding Path=IsReadOnly, Converter={StaticResource InverseBooleanConverter}}"

Converter:

[ValueConversion(typeof(bool), typeof(bool))]
    public class InverseBooleanConverter: IValueConverter
    {
        #region IValueConverter Members

        public object Convert(object value, Type targetType, object parameter,
            System.Globalization.CultureInfo culture)
        {
            if (targetType != typeof(bool))
                throw new InvalidOperationException("The target must be a boolean");

            return !(bool)value;
        }

        public object ConvertBack(object value, Type targetType, object parameter,
            System.Globalization.CultureInfo culture)
        {
            throw new NotSupportedException();
        }

        #endregion
    }

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