I’m using a custom route in my ASP.NET MVC app (/lang/{culture}/{controller}/{action}/{id}) and in my base controller, I’m detecting the presence of a value for the culture parameter and setting the current thread culture. However, if someone manages to navigate to a language that doesn’t have any resources, rather than silently falling back to the default culture, I want to present a message indicating the lack of language support.
How can I detect if the current culture has no resources specified rather than silently falling back to the default?
The issue is that in practice it’s complicated to programmatically determine whether you have localizations for a given culture. You may have satellite assemblies for a given culture for one assembly, but not for another. And worse, one satellite assembly may contain translations for some resources, but not all. This may be intentional: for en-GB you may prefer to only take an “override rather than duplicate” approach and define only a few resources here and there, only where you differ from your base English.
So the simplest and clearest approach may be to maintain a hard-coded master list of supported cultures in your application code, and then just base your language support alerting logic on this list. When you add a new localization, you’ll need update that list in code. But most of us do localization by checking-in new resource files into the solution anyway–there already isn’t a complete separation between code and localized resources.