IQueryable Extensions

Conditional 'Select' and 'Where' extensions, in order to resolve  some condition before query executed on provider (database)

sample 
``var item = context.Articles
                                  .SelectIf(request.Culture == "fa-ir",
                                            q => new {q.Id, Abstract = q.Abstract_fa},
                                            q => new {q.Id, Abstract = q.Abstract_en})
                                  .FirstOrDefault(q => q.Id == request.ArticleId);``