RazorEngine - Use Layout and Html.Raw

Question

I'd like to use the following Razor template with RazorEngine:

@{
    Layout = null;
}

@Html.Raw(MyNamespace.MyClass.SomePropertyWithHtml)

When I call it I get 2 errors - one complaining it can't handle Layout, and another complaining it doesn't know how to deal with the Html helper.

There are other questions and answers here suggesting this is possible in v3, and I'm using the current package on NuGet - v3.0.8 - but it isn't clear how this is done. Currently I'm calling it like so:

string html = RazorEngine.Razor.Parse(File.ReadAllText(path));

Other answers suggest using Razor.SetBaseTemplate first, which does not appear in current source or the 3.0 branch on git. Looking at the code I see code referencing layouts and sections, but the layout code appears to depend on resolving a template by name, while what I'm trying to do doesn't even need to resolve a template - I just need it to cope with the Layout = null. The code also includes a MvcTemplateBase that appears to offer an HtmlHelper in the Web project - but it's the sole class in that project and not referenced anywhere in the Web or Core projects.

This similar question: RazorEngine issues with @Html

Just links to the homepage saying you can find out more there - the homepage is just a short sentence describing the project.

So, how do I parse the above Razor view with RazorEngine v3.0?

Attalanta

Oh, you're using RazorEngine...One thing to keep in mind is that Razor isn't MVC. A lot of work has been done with the new RazorEngine but Antaris has been really busy lately. You should be able to use @inherits MvcTemplateBase<T> at the top of your file to use it. – Hesiod

Thanks for the suggestion. I realize Razor and MVC are separate, but my goal is to use the same MVC Razor templates inside and outside the normal ASP.Net pipeline. The version on NuGet doesn't contain a class named MvcTemplateBase. The latest version on Git does, but it isn't generic - it's just MvcTemplateBase. If I add a line like @inherits RazorEngine.Razor.MvcTemplateBase I get an Exception in TemplateService.SetModelExplicit complaining the template type has no property named Model. Ideas? – Attalanta

Answer 1

The Layout property and the Html helper are not a part of TemplateBase, and the implementation of MvcTemplateBase that is a part of the latest version of RazorEngine (v3.4.1) appears incomplete (InitHelpers doesn't seem to initialize the helpers?). You'll need to create your own base template that implements these features.

As you noted, v3+ versions do not include a Razor.SetBaseTemplate method. You can set a base template type in the current version like so:

var config = new RazorEngine.Configuration.TemplateServiceConfiguration
    {
        BaseTemplateType = typeof(MyTemplateBase<>)
    };

using (var service = new RazorEngine.Templating.TemplateService(config))
{
    Razor.SetTemplateService(service);
    return MvcHtmlString.Create(Razor.Parse<TModel>(templateText, model));
}

Should you need to initialize helpers, it may be helpful to override CreateInstance in a custom implementation of IActivator, which can be provided to the TemplateServiceConfiguration like the BaseTemplateType:

var config = new RazorEngine.Configuration.TemplateServiceConfiguration
    {
        BaseTemplateType = typeof(MyTemplateBase<>),
        Activator = new MyActivator()
    };

Succinic

Hmm which version of RazorEngine are you using? Or did you derive MvcTemplateBase as your own class? The current source doesn't have a generic version of MvcTemplateBase: github.com/Antaris/RazorEngine/blob/master/src/Web/… – Attalanta

That's a homegrown implementation of MvcTemplateBase. The point of the above is to demonstrate that you still can in fact set a base template to inherit all of your views from, which will allow you to implement the Html helper, base Layout functionality, or whatever you should need that RazorEngine's TemplateBase doesn't offer out of the box. – Succinic

Clarified my answer above. I noticed earlier that this question is over 2 years old, but I think this still answers it. Let me know if anything is unclear. Maybe this'll still help someone. – Succinic