When will T4MVC support Razor with explicit HtmlHelpers for rendering partials?

Question

I've been using T4MVC for some time now and love the "explicit HtmlHelpers for rendering partials" feature, which by default is switched off. I am using T4MVC version 2.6.40.

I recently upgraded to MVC3 and noticed that no explicit HtmlHelpers are generated for Razor partials, so I looked at the source code of the T4MVC text template and found a method named "GetPartials" which has a line of code as folows:

var parts = GetControllers()
        .Select(m => m.ViewsFolder)
        .SelectMany(m => m.Views)
        .Where(m => m.Value.EndsWith(".ascx"));

So it is clear that Razor views are not supported.

I'd also like to mention that when running the T4 template (right-click > run custom tool) I get a compiler warning stating: "The C# 2.0 and C# 3.5 compilers are no longer supported. Templates will always be compiled with the version 4 compiler instead of 'v3.5' as specified."

This relates to line 18 where the template language attribute has a value of "C#v3.5". Why does it have to have an explicit version dependency? Can it not just be "C#"?

Apologies for asking two seperate questions in one post.

Answer 1

I just released T4MVC 2.6.42 to address this. You can get it from Codeplex or from NuGet.

Note that in order to have a razor file be detected as a partial by T4MVC, its name needs to start with an underscore (e.g. _foo.cshtml). Without this restriction, we would end up creating helper methods for all views, which would pollute things and not add value. Note that prefixing partial Razor views with _ is generally recommended by the MVC team.

As for the warning, it's unrelated and is benign. To get rid of it, just change language="C#v3.5" to language="C#". I can't make that change in the official version as that would make it break when running on 3.5 (and I don't want to maintain two separate versions just for that).

Answer 2

The compiler warning you receive is just that, a warning. It is not preventing T4MVC from working.

As for supporting Razor, you've found the appropriate code in the template - simply modify it.

var parts = GetControllers()
        .Select(m => m.ViewsFolder)
        .SelectMany(m => m.Views)
        .Where(m => m.Value.EndsWith(".ascx") || m.Value.EndsWith(".cshtml") || m.Value.EndsWith(".vbhtml"));

I'd give that a try.

It's just a T4 Template, not magic. All it contains is simple c# code that gets project info from the Visual Studio environment and generates some fairly simple c# code.