reference a double resource inside another double resource

I would like to reference a resource of Double inside another Double resource, something like this:

<sys:Double x:Key="width">100</sys:Double>

<sys:Double x:Key="height">{Static开发者_如何学编程Resource width}</sys:Double>

How can I do this?

I doubt that this is possible, you are referencing an atomic data-type that can contain nothing else than a numeric value which is neither a field nor a property. To allow that you probably need to create your own datatype.

Edit: Normally you should be able to use a DynamicResource for this:

<DynamicResource x:Key="height" ResourceKey="width"/>

(Visual Studio won't like this but it should compile and work)

Well, i'm not sure the example you're giving could work, since i'm not able to do a binding to "sys:Double".

but other than that, the answer to you question: you can use a convertor, and it's pretty simple. add this class:

class DoubleConvertor : IValueConverter
{

    public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
    {
        return value;
    }

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

and than reference this class in the xaml (make sure to use the xmlns of your project first):

<local:DoubleConvertor x:Key="DoubleConvertor" />

now in your binding you can do something like:

<UserControl Height="{Binding path={StaticResource width}, Converter={StaticResource DoubleConvertor} />