How do I create SEO-Friendly urls in ASP.Net-MVC

MVC stands for "Model View Controller" and while those concepts aren't what you're asking about, you generally can wire up URL's like you see above quite easily

So for example by default the URL's look like the following

http://www.somesite.com/controller/view/

where controller refers to the controller class within your project, and view refers to the page/method combination within the controller. So for example you could write the view to take in an input and look something like the following

http://www.somesite.com/widget/productid/1234/

Now as for SEO Friendly URL's, that's just useless sugar. You author your controller such that it adds harmless cruft to the end of the URL.

So for example, you'll notice that the following three ways to get to this question produce the same result:

How do I create SEO-Friendly urls in ASP.Net-MVC

How do I create SEO-Friendly urls in ASP.Net-MVC

How do I create SEO-Friendly urls in ASP.Net-MVC

Stack Overflow has authored their route values such that the bit that occurs after the question ID isn't really necessary to have.

So why have it there? To increase Google PageRank. Google PageRank relies on many things, the sum total of which are secret, but one of the things people have noticed is that, all other things being equal, descriptive text URL's rank higher. So that's why Stack Overflow uses that text after the question number.

Create a new route in the Global.asax to handle this:

        routes.MapRoute(
            "productId",                  // Route name
            "productId/{id}/{name}",      // URL with parameters
            new { controller = "Home", action = "productId", id = 1234, name = widget }  // Parameter defaults
        );

Asp.Net MVC has routing built in, so no need for the Url Rewriter.

Be careful when implementing routes with names in them, you need to validate that the name coming in is correct or you can end up harming your SEO-Ranking on the page by having multiple URIs share the same content, either set up a proper canonical or have your controller issue 301s when visiting the 'wrong' URI.

A quick writeup I did on the latter solution can be found at:
http://mynameiscoffey.com/2010/12/19/seo-friendly-urls-in-asp-net-mvc/

Some info on canonicals:
http://googlewebmastercentral.blogspot.com/2009/02/specify-your-canonical.html