URL routing was a capability we first introduced with
ASP.NET 3.5 SP1, and which is already used within ASP.NET MVC applications to
expose clean, SEO-friendly “web 2.0” URLs. URL routing lets you configure
an application to accept request URLs that do not map to physical files.
Instead, you can use routing to define URLs that are semantically meaningful to
users and that can help with search-engine optimization (SEO).
For example, the URL for a traditional page that displays
product categories might look like below:
Using the URL routing engine in ASP.NET 4 you can now
configure the application to accept the following URL instead to render the
With ASP.NET 4.0, URLs like above can now be mapped to both
ASP.NET MVC Controller classes, as well as ASP.NET Web Forms based pages.
You can even have a single application that contains both Web Forms and MVC
Controllers, and use a single set of routing rules to map URLs between them.
Please read my previous URL Routing with ASP.NET 4 Web Forms blog post to learn
more about how the new URL Routing features in ASP.NET 4 support Web Forms