Set value to null in WPF binding

Question

please take a look at the following line

This Price property from above is a Decimal?

Answer 1

I am using .NET 3.5 SP1 so it's very simple:

Which stands for (thanks Gregor for your comment):

sys is the imported xml namespace for System in mscorlib:

xmlns:sys="clr-namespace:System;assembly=mscorlib"

Hope that helped.