Registering an HTML-derived content type with the HTML editor without a package?

Question

I'm trying to register a custom content type, similar to this question on MSDN forums: I want to register a custom extension that is essentially an HTML file, e.g.:

[Export]
[DisplayName("My Custom Markup")]
[Name("mycustom")
[BaseDefinition("html")]
internal static ContentTypeDefinition MyCustomContentType;

[Export]
[FileExtension(".mycustom")]
[ContentType("mycustom")]
internal static FileExtensionToContentTypeDefinition MyCustomFileExtensionDefinition;

So by specifying BaseDefinition as html, I am able to get HTML highlighting in .mycustom files, unfortunately I get nothing else, in particular, the HTML intellisense. From the above link it seems that the only way to have Visual Studio recognize custom extensions as a specific editor type, but I'd have to hack the registry (or more specifically, provide this via the ProvideEditorExtension attribute, but it's only applicable on a VSPackage).

So my question is, basically, is there an alternative way to register a custom extension to an editor programmatically, but without creating a custom VSPackage for it? Other than hacking the registry, of course?

(I could be totally wrong with the approach, in which case your help is very much appreciated!)

Answer 1

The easiest way is to use the technique demoed here:

http://blogs.msdn.com/b/noahric/archive/2010/03/01/new-extension-css-is-less.aspx

This is effectively "hacking the registry" but in a supported way. You're simply wrapping the needed keys in a .pkgdef file (essentially a .reg file) that can be contained in an editor extension.