public string AddSubject(string jsonString = "{\"id_class\":\"2\",\"id_group\":\"\",\"id_teaher\":\"1\",\"name\":\"Francuski\"}") { AddSubjectPostViewModel addSubject = JsonConvert.DeserializeObject <AddSubjectPostViewModel>(jsonString); Subject s = new Subject() { Person = db.GetPerson(addSubject.ID_Teaher), Group = addSubject.ID_Group != null?db.GetGroup(addSubject.ID_Group) : null, Class = db.GetClass(addSubject.ID_Class), Name = addSubject.Name }; db.AddSubject(s); return("Dodano"); }