c# - 更改 XAML 中的绑定(bind)值

Question

我需要在 XAML 中进行一些复杂的绑定(bind)。我有一个 DependencyProperty typeof(double);我们将其命名为 SomeProperty。在我的控件的 XAML 代码中的某处，我需要使用整个 SomeProperty 值，某处只使用一半，某处 SomeProperty/3，等等。

我该如何做:

<SomeControl Value="{Binding ElementName=MyControl, Path=SomeProperty} / 3"/>

:)

期待。

Answer 1

使用除法ValueConverter :

public class DivisionConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        int divideBy = int.Parse(parameter as string);
        double input = (double)value;
        return input / divideBy;
    }

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

<!-- Created as resource -->
<local:DivisionConverter x:Key="DivisionConverter"/>

<!-- Usage Example -->
<TextBlock Text="{Binding SomeProperty, Converter={StaticResource DivisionConverter}, ConverterParameter=1}"/>
<TextBlock Text="{Binding SomeProperty, Converter={StaticResource DivisionConverter}, ConverterParameter=2}"/>
<TextBlock Text="{Binding SomeProperty, Converter={StaticResource DivisionConverter}, ConverterParameter=3}"/>