Razor is a view-engine option for ASP.NET that can be used to easily embed C# or VB code within an HTML page. This is “bin” deployable and free.
To get started, download the items under the Tools section below. This section includes items from Microsoft (WebMatrix) as well as a module to run Razor within DotNetNuke. It should be noted that in order to use Razor you will need to have your DotNetNuke site running under .NET framework version 4.0 which is currently not a requirement for DotNetNuke installs.
As part of the DotNetNuke Razor Hackathon
was created that demonstrates how to use the DotNetNuke Razor Host to create, run and even deploy Microsoft Razor applications in DotNetNuke.