How to change default view location scheme in ASP.NET MVC?

Question

I want to change view locations at runtime based on current UI culture. How can I achieve this with default Web Form view engine?

Basically I want to know how implem

Answer 1

Below is a localized view engine without the rewrite.

In a nutshell, the engine will insert new locations into the view locations everytime a view is looked up. The engine will use the two character language to find the view. So if the current language is es (Spanish), it'll look for ~/Views/Home/Index.es.cshtml.

See code comments for more details.

A better approach would be to override the way view locations are parsed, but the methods are not overridable; maybe in ASP.NET MVC 5?

public class LocalizedViewEngine : RazorViewEngine
{
    private string[] _defaultViewLocationFormats;

    public LocalizedViewEngine()
        : base()
    {
        // Store the default locations which will be used to append
        // the localized view locations based on the thread Culture
        _defaultViewLocationFormats = base.ViewLocationFormats;
    }

    public override ViewEngineResult FindPartialView(ControllerContext controllerContext, string partialViewName, bool useCache)
    {
        AppendLocalizedLocations();
        return base.FindPartialView(controllerContext, partialViewName, useCache:fase);
    }

    public override ViewEngineResult FindView(ControllerContext controllerContext, string viewName, string masterName, bool useCache)
    {
        AppendLocalizedLocations();
        returnbase.FindView(controllerContext, viewName, masterName, useCache:false);
    }

    private void AppendLocalizedLocations()
    {
        // Use language two letter name to identify the localized view
        string lang = Thread.CurrentThread.CurrentUICulture.TwoLetterISOLanguageName;

        // Localized views will be in the format "{action}.{lang}.cshtml"
        string localizedExtension = string.Format(".{0}.cshtml", lang);

        // Create an entry for views and layouts using localized extension
        string view =  "~/Views/{1}/{0}.cshtml".Replace(".cshtml", localizedExtension);
        string shared =  "~/Views/{1}/Shared/{0}".Replace(".cshtml", localizedExtension);

        // Create a copy of the default view locations to modify
        var list = _defaultViewLocationFormats.ToList();

        // Insert the new locations at the top of the list of locations
        // so they're used before non-localized views.
        list.Insert(0, shared);
        list.Insert(0, view);
        base.ViewLocationFormats = list.ToArray();
    }
}