How to format TimeSpan in XAML

Question

I am trying to format a textblock which is bound to a TimeSpan property. It works if the property is of type DateTime but it fails if it is a

Answer 1

Just to add to the pool, I'm successfully using this binding to display a TimeSpan in a production WPF app:

Binding="{Binding Time, Mode=TwoWay, StringFormat=\{0:h\\:mm\}}"

Took some tries to get the backslashes right :)