c# - 如何在某些情况下禁用转换器

Question

当 autosize 为 false 时如何禁用以下转换器。我应该将什么代码放入什么都不做区域。

[ValueConversion(typeof(Boolean), typeof(Double))]
public class ConvertAutoSize2HeightWidth : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        Boolean autosize = (Boolean)value;
        if (autosize)
            return Double.NaN;
        else
            //**do nothing**
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}

Answer 1

可以尝试返回Binding.DoNothing .

A binding source property or a converter can return Binding.DoNothing to instruct the binding engine not to perform any action. For example, to instruct the binding engine not to transfer a value to the binding target, not to move to the next Binding in a PriorityBinding, or not to use the FallBackValue or default value.