public void Add(Folder model, string UserID = "") { var _group = groupDal.getMany(a => a.ID == model.Group.ID).Include(a => a.Users).FirstOrDefault(); if (_group != null) { var _member = _group.Users.Where(a => a.UserID == UserID).FirstOrDefault(); if (_member != null && (_member.Status == Status.Owner || _member.Status == Status.Manager)) { model.Group = _group; model.CreateDate = DateTime.Now; base.Add(model); } else { throw new Exception("Authorization error"); } } else { throw new Exception("Group not found"); } }