epi11-loc-provider-fix.cs

    [InitializableModule]
    [ModuleDependency(typeof(ServiceContainerInitialization))] // used to override default provider
    public class CustomProviderBasedLocalizationService : ProviderBasedLocalizationService, IConfigurableModule
    {
        private static LocalizationService _localizationService;

        public CustomProviderBasedLocalizationService() : this(null) { }

        public CustomProviderBasedLocalizationService(ResourceKeyHandler keyHandler) : base(keyHandler) { }

        public new void ConfigureContainer(ServiceConfigurationContext context)
        {
            // register as a factory
            context.Services.AddSingleton(typeof(LocalizationService),
                                          locator =>
                                              CreateCustomProviderBasedLocalizationService(locator.GetInstance<ResourceKeyHandler>(),
                                                                                           locator.GetInstance<LocalizationOptions>(),
                                                                                           locator));
        }

        protected override string LoadString(string[] normalizedKey, string originalKey, CultureInfo culture)
        {
            var list = ProviderList.ToList(); // important fix for collection was modified issue
            foreach(var provider in list)
            {
                var str = provider.GetString(originalKey, normalizedKey, culture);
                if(str != null)
                    return str;
            }

            return null;
        }

        public static LocalizationService CreateCustomProviderBasedLocalizationService(
            ResourceKeyHandler keyHandler,
            LocalizationOptions localizationOptions,
            IServiceLocator serviceLocator)
        {
            if(_localizationService != null)
                return _localizationService;

            ProviderBasedLocalizationService localizationService = new CustomProviderBasedLocalizationService(keyHandler);
            foreach(var providerFactory in localizationOptions.Providers)
                localizationService.AddProvider(providerFactory.Build(serviceLocator));

            localizationService.FallbackBehavior = localizationOptions.FallbackBehavior;
            localizationService.FallbackCulture = localizationOptions.FallbackCulture;
            _localizationService = localizationService;

            return _localizationService;
        }
    }