public void Update(EditDiscussionViewModel model) { var mapper = new MapperConfiguration(c => { c.CreateMap <EditDiscussionViewModel, Discussion>(); c.IgnoreUnmapped(); c.CreateMap <UserViewModel, User>(); c.IgnoreUnmapped(); c.CreateMap <CategoryViewModel, Category>(); c.IgnoreUnmapped(); }).CreateMapper(); var discussion = mapper.Map <EditDiscussionViewModel, Discussion>(model); _discussionsRepository.Update(discussion); }