mvc-5-routing-localization

Simple localization and translation for both conventional and attribute static routing.

Features

Normal Route("~/invest") automatically(can opt out) gets a language prefix, such as /invest for default language, and e.g. /de/invest for german language. You can achieve the same for conventional routing.

For more control and/or url translation use LocalizeRoute("..."), so you can get /de/investieren, or disable route localization(opt out).

The effect is that you get Thread.CurrentThread.CurrentCulture and CurrentUICulture set appropriately during controller initialization.

Setup

Let's say we have a couple of languages we want to support, stored in application config, accessible like his:
ConfigurationManager.AppSettings["SupportedCultures"] -> "en,de"

We have a default culture like so:
ConfigurationManager.AppSettings["DefaultCulture"] -> "en"'

Have a resource files for these languages containing url path segments translated, e.g. for key 'invest' have it with default value 'invest', and in german resource file as 'investieren'

Add global filter:

filters.Add(new CultureFilter(ConfigurationManager.AppSettings["DefaultCulture"]);

Conventional routing

routes.MapRoute(
  name: "DefaultWithCulture",
  url: "{culture}/{controller}/{action}/{id}",
  defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
  constraints: new { culture = new CultureConstraint(defaultCulture: ConfigurationManager.AppSettings["DefaultCulture"]) }
  );

routes.MapRoute(
	name: "Default",
	url: "{controller}/{action}/{id}",
	defaults: new { culture = DefaultCulture, controller = "Home", action = "Index", id = UrlParameter.Optional }
);

Do this in same order in areas route registration too.

Attribute routing

In order for conventional and attribute routing to work together, initialize them in this order in global.asax.cs :

RouteTable.Routes.MapLocalizedMvcAttributeRoutes();
AreaRegistration.RegisterAllAreas();
RouteConfig.RegisterRoutes(RouteTable.Routes);

By default, all normal routes are localized by adding a culture prefix e.g. for

[Route("~/invest")]

you have 2 routes generated:
~/{culture}/invest
~/invest (this one has a default route value of {culture} -> 'en')

Default culture urls by default have no language prefix - you can change this by setting PrefixDefaultCulture in web.config to true, so you will have /en/invest.

To have more control, use LocalizedRoute, usually for 2 scenarios:

1. Translate url path

[LocalizedRoute("~/invest")]
ActionResult Index() { ... }

generates these routes:
~/de/investieren
~/invest

2. Have a route that does not get prefix-localized, e.g. to permanent-redirect an old url to new one for SEO reasons.

For example if you need to redirect /investing to /invest. You can still opt out of url translation.

[LocalizeRoute("~/investing", explicitCulture: "en", translateUrl: false)
ActionResult Index_Old_en()
{
	return RedirectToActionPermanent("Index");
}

Ideas from post https://stackoverflow.com/questions/32764989/asp-net-mvc-5-culture-in-route-and-url