Whenever I teach my students about the navigation web controls (Menu, TreeView and SiteMapPath) and sitemap files in ASP.NET, it's a guarantee that someone is going to ask me if you can use them with querystrings. So when I say "no", I can feel the whole room sigh with disappointment. I can't blame them - it's a shame that this wasn't built in.
Fortunately for us, ASP.NET gives you the ability to create your own sitemap provider class so that you can extend the functionality of your sitemap files any way you like. As a result, we can create our own code to give our sitemap files the ability to use querystring parameters. My good friend, Jason Gaylord, shares with us a post that he found that does exactly that; he also gives you some VB code to help you create the sitemap provider to make this work.
This should lead to less sighs of disappointment from my classes moving forward. Thanks, Jason!