.CSHTML File Extension
File TypeASP.NET Razor Web Page
What is a CSHTML file?
C# ("C sharp") HTML webpage file used by Razor, an ASP.NET view engine used for generating Web pages for a user's Web browser; similar to a standard ASP.NET webpage (.ASP or .ASPX file), but uses a slightly different syntax; runs on a Web server, which generates the HTML for the client Web browser; can be programmed with syntax highlighting and Intellisense code suggestions using Microsoft Visual Studio.
CSHTML files are similar to .VBHTML (Visual Basic HTML) files, but they use syntax that is closer to the C# language rather than the Visual Basic language.
NOTE: Razor offers new templating syntax operations in addition to those supported by the standard ASP.NET MVC default view engine.