public DataTable LoadNguoiDat()
        {
            DAO_NguoiDat nd = new DAO_NguoiDat();
            DataTable    dt = new DataTable();

            dt = nd.LoadNguoiDat();
            return(dt);
        }
        public int XoaNguoiDat(string id, int stt)
        {
            int          kq = 0;
            DAO_NguoiDat kh = new DAO_NguoiDat();

            kq = kh.DelNguoiDat(id, stt);
            return(kq);
        }
        public int ThemNguoiDat(NguoiDat nd)
        {
            int          kq = 0;
            DAO_NguoiDat kh = new DAO_NguoiDat();

            kq = kh.AddNguoiDat(nd);
            return(kq);
        }