Visual Studio treat custom extension as CSharp -

I have files with a custom extension. MSCX which is actually a CSRP file, I have to complete these files in Visual Studio 2012, but these files are considered as plain text when I call them VS. I open in

I have tried to create custom MEF extensions, which allow me to treat files as content-type based on CSSRP, but I do not have autocomplete or code formatting for these documents Are getting. I may need to open a custom CSHP classifier for my custom content type, but I'm not sure. Can anyone help?

The custom content type is below:

  Fixed class ContentType {public const string name = "cscript"; [Export] [Name (name)] [DisplayName ("CSHRP script")] [BaseDefinition ("CSHRP")] Public Static Content Type Definition CSharpContentType = null; [Export] [Content Type (Name)] [File Extension (".mcsx")] Public Static File ExtensionTontent Definition CSharpFileExtension = null; }    
 
 
 Thank you for 'ego' on VS forums:  
 You can add custom extension file through the following way:  
  
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