我拥有的是一个具有IsReadOnly属性的对象。如果此属性为true，我想将按钮上的IsEnabled属性设置为false(例如)。
我愿意相信我可以像IsEnabled="{绑定路径=!IsReadOnly}”，但这与WPF不兼容。
我是否不得不经历所有的样式设置?对于将一个bool值设置为另一个bool值的倒数这样简单的事情来说，似乎太啰嗦了。
<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>
你可以使用ValueConverter来反转bool属性。
XAML:
IsEnabled="{Binding Path=IsReadOnly, Converter={StaticResource InverseBooleanConverter}}"
转换器:
[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
}
这个方法也适用于可为空的bool。
[ValueConversion(typeof(bool?), typeof(bool))]
public class InverseBooleanConverter : IValueConverter
{
#region IValueConverter Members
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
if (targetType != typeof(bool?))
{
throw new InvalidOperationException("The target must be a nullable boolean");
}
bool? b = (bool?)value;
return b.HasValue && !b.Value;
}
public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
return !(value as bool?);
}
#endregion
}
