asp.net mvc 3 - Razor Nested Layouts with Cascading Sections

Question

I have an MVC3 site using Razor as its view engine. I want my site to be skinnable. Most of the possible skins are similar enough that they can derive from a shared master layout.

Therefore, I am considering this design:

However, I would like to be able to call RenderSection in the bottom layer, _Common.cshtml, and have it render a section that is defined in the top layer, Detail.cshtml. This doesn't work: RenderSection apparently only renders sections that are defined the next layer up.

Of course, I can define each section in each skin. For instance, if _Common needs to call RenderSection("hd") for a section defined in Detail, I just place this in each _Skin and it works:

@section hd {
    @RenderSection("hd")
}

This results in some duplication of code (since each skin must now have this same section) and generally feels messy. I'm still new to Razor, and it seems like I might be missing something obvious.

When debugging, I can see the complete list of defined sections in WebViewPage.SectionWritersStack. If I could just tell RenderSection to look through the entire list before giving up, it would find the section I need. Alas, SectionWritersStack is non-public.

Alternatively, if I could access the hierarchy of layout pages and attempt execution of RenderSection in each different context, I could locate the section I need. I'm probably missing something, but I don't see any way to do this.

Is there some way to accomplish this goal, other than the method I've already outlined?

Answer 1

This is in fact not possible today using the public API (other than using the section redefinition approach). You might have some luck using private reflection but that of course is a fragile approach. We will look into making this scenario easier in the next version of Razor.

In the meantime, here's a couple of blog posts I've written on the subject:

• http://blogs.msdn.com/b/marcinon/archive/2010/12/08/optional-razor-sections-with-default-content.aspx
• http://blogs.msdn.com/b/marcinon/archive/2010/12/15/razor-nested-layouts-and-redefined-sections.aspx