@Ragims,
No matter whether Scott Hanselman might come come and kick my a$$ or not, I embed any and all code that I need in my Views, inside <% %> tags.
That being said, I try to get most processing done in a model, triggered from the controller code.
I don't think you should use codebehind, but embed what you need in the page itself.
Keep it as clean as you can, and use server side comments inside
<%
// this is c# comment
%>
when you can't keep it clean.
You will be better served doing stuff in a model or controller in the long run.
Codebehind vs CodeInPlace conveys no advantages that I know of.
CodeInPlace at least lets you see the code in the context of the html.
Yeah, Yeah, I know it reminds us all of the asp days. Some things in those days were pretty clear.
ymmv