Solved. So, what is needed to be done:
create public class with public properties inside. Properties names should match post/get values in my form
add this:
@inherits ViewPage<BillionaireServiceStackRazorSelfHosting.MyClass>
to cshtml
After form submit, corresponding properties are set. I don't know if this is good way (please correct me if it doesn't), but I've added some code to "set" handler inside MyClass property, instead of adding code to cshtml that uses captured values.
Everything seems to be working as I wanted to.