How to declare a namespace in WPF XAML?

Question

I am trying to use in WPF a validating input of databound controls with validation rules. In the code behind file of a wpf window I have a class:

public clas         


        

Answer 1

At the top of your XAML file, you need to declare what your "local" namespace is; alongside the default Microsoft XAML stuff. Something like this:

xmlns:local="clr-namespace:YourApplication"

Note this assumes that "posintValidationRule" is defined at the root namespace in "YourApplication".