Because your question is too underdefined and there is nothing like "web matrix's cshtml". That one is the extension associated with Razor view engine
] in ASP.NET MVC3
] and above. And you will get nothing with just a login form
. ASP.NET authentication
] is more complex than that.
But if you start an MVC3 project in Visual Studio (not the empty project template), and you choose the internet site (form authentication), you will get a good sample. (http://msdn.microsoft.com/en-us/library/ee377605.aspx)