public void Handle(ConferenceEditModel form) { Conference conf = _repository.GetById(form.Id); conf.ChangeName(form.Name); foreach (var attendeeEditModel in GetAttendeeForms(form)) { Attendee attendee = conf.GetAttendee(attendeeEditModel.Id); attendee.ChangeName(attendeeEditModel.FirstName, attendeeEditModel.LastName); attendee.Email = attendeeEditModel.Email; } }