private static void GetLanguagesListCallback(IEnumerable <Language> languages) { if (languages != null) { var newLanguages = new List <Language>(); var existingLanguageCultures = _languageRepository.GetAllLanguages().Select(l => l.Culture); foreach (var language in languages) { if (!existingLanguageCultures.Contains(language.Culture)) { newLanguages.Add(language); } } _languageRepository.AddLanguagesCollection(newLanguages); } InvokeCallbackWithLanguageListParameter(_languageRepository.GetAllLanguages()); }