ASP.NET MVC – Add custom locations to the View Engine default search patterns

Errore 403 - forbidden dopo aver pubblicato una applicazione ASP.NET MVC su IIS 7: come risolvere

One of the things I like most when developing ASP.NET application using the MVC model (if you don’t know yet what it is, read here) is the emphasis put to the project’s folder structure: the separation between the three logical aspects is reflected to the directory tree, expecially – since the Model is often injected from external libraries and their abstraction layers – the /Controllers/ and /Views/ folders, hosting respectively the input handlers and the user interface of our application.

Among these, the /Views/ folder plays a peculiar role in relation with the filesystem because it is looked by the View Engine to retrieve the View .cshtml and/or .aspx files implicitly or expicitly referenced by each Controller. The search is handled using a set of predefined patterns that come by the name of default location scheme. Here’s a portion of it, used by the Razor View Engine to lookup the standard Views:

The full location scheme, including the default patterns for Partial Views, Area Views, Master Views et. al., can be seen by looking at this page.

Back to our example, we can notice two placeholders{0} and {1}, referring to the Action and its Controller. What happens under the hood is the View Engine checking for the presence of a suitable View file in these folder paths, starting with the most specific ones and then looking in the directory hosting the shared views.

Question is: can we add other paths? Or, to be more specific: can we edit these lists, maybe adding one of more folders to reflect the folder structure we used to organize our Views, or are we forced to use the default locations to avoid errors like the following one?

The view ‘YourView’ or its master was not found or no view engine supports the searched locations. The following locations were searched:

error-view-engine

Most answers that can be found on the web offer solutions relying to rather complex approaches, such as creating a new View Engine by extending the RazorViewEngine or the WebFormViewEngine, clearing & rewriting the   collection, and other not so developer-friendly techniques.

Luckily enough, there’s a simple yet effective method to alter the default location scheme collection with few lines of code and without having to create or extend any class: all we have to do is to add the following lines to the Global.asax‘s Application_Start method:

The above example adds a folder reference (with or without Controller) to the default search pattern array for either the Views and Partial Views by using a rather inobtrusive, lightweight approach. You can also add other folders to one or both these arrays, and/or to any other Views collection referenced by the already mentioned page.

That’s it fow now: happy coding!

About Ryan

IT Project Manager, Web Interface Architect and Lead Developer for many high-traffic web sites & services hosted in Italy and Europe. Since 2010 it's also a lead designer for many App and games for Android, iOS and Windows Phone mobile devices for a number of italian companies. Microsoft MVP for Development Technologies since 2018.

View all posts by Ryan

2 Comments on “ASP.NET MVC – Add custom locations to the View Engine default search patterns”

  1. Thanks very much for your article but when I try this
    var razorEngine = ViewEngines.Engines.OfType().First();
    gives

    System.InvalidOperationException: Sequence contains no elements ??
    Any ideas ??

    1. Hello and sorry for the late reply: for MVC5 I guess you can try to replace the following 4 lines of the sample code with these:

      var razorEngine = ViewEngines.Engines.OfType().FirstOrDefault();
      if (razorEngine == null)
      {
      razorEngine = new RazorViewEngine();
      ViewEngines.Engines.Add(razorEngine);
      }

      Please try it and let me know if it solves your issue, so I’ll update the post as well.

  2. Pingback: Multisite WFFM Form Markup using MVC Areas | jammykam

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