Yeh the title practically says it all. I'll be developing an ecommerce website using .NET technology for my upcoming school project, and I wawnt to make my first ASP site an impressive one so I'm thinking of actually coming out with a cool design and code it to be valid xhtml, and the way layout images are kept in CSS files, BUT I'm not sure whether this is even possible. First thing I need to know is whether the ASP codes are even valid xhtml in the first place, anyone knows?

I was thinking of attaching the external CSS file to the master page, like how you usually code a valid xhtml/css website.

Well from what I know about ASP it is similar to PHP in the way that the ASP codes are parsed server side, then the server sends the resulting output to the browser whenever the page is requested. Therefore as long as the resulting output is valid you should be fine.

A way to check this is to view your ASP page after you've loaded it on a server, and view the source through the browser and you should notice all your ASP coding has disappeared.

In theory, it's not possible since validation will always through warnings on its hidden input names that start with an underscore, which are generated by .NET code: