In DD4T, when should I use ModelControllerBase, and when TridionControllerBase

Question

In learning DD4T, I have made reference to Albert Romkes' article DD4T Continued: rendering component presentations where he gives an example using TridionControllerBase.

So far, most of the answers to my question How do I make use of DD4T's provided ViewModels? have used examples with ModelControllerBase

What is the difference between these techniques, and when should I use one and when the other?

Answer 1

The biggest difference is the inclusion of IViewModelFactory. This allows ModelControllerBase to return the Model converted to your associated View Model type. TridionControllerBase returns the Model as a base Tridion type e.g. Page and ComponentPresentation.

Compare for example:

TridionControllerBase

[HandleError]
public virtual ActionResult Page(string url)
{
      url = AddWelcomePageToUrl(url);
      IPage page = GetPage(url);
      if (page == null) { throw new HttpException(404, "Page cannot be found"); }
      return View(GetViewName(page), page);
}

ModelControllerBase

[HandleError]
public virtual ActionResult PageModel(string url)
{
      url = AddWelcomePageToUrl(url);
      IPage page = GetPage(url);
      if (page == null) { throw new HttpException(404, "Page cannot be found"); }
      IViewModel pageViewModel = ViewModelFactory.BuildViewModel(page);
      return View(GetViewName(page), pageViewModel);
}