public bool KiemTraTonTai(string str, int loaiKT)
        {
            clsNguoiDung_DAO dao = new clsNguoiDung_DAO();

            return(dao.KiemTraTonTai(str, loaiKT));
        }
        public bool CapNhatTaiKhoan(bool TrangThai, string MaNV)
        {
            clsNguoiDung_DAO dao = new clsNguoiDung_DAO();

            return(dao.CapNhatNguoiDung(TrangThai, MaNV));
        }
        public bool TaoTaiKhoan(clsNguoiDung_DTO nd)
        {
            clsNguoiDung_DAO dao = new clsNguoiDung_DAO();

            return(dao.TaoTaiKhoan(nd));
        }
        public bool CapNhatTaiKhoan(clsNguoiDung_DTO nd)
        {
            clsNguoiDung_DAO dao = new clsNguoiDung_DAO();

            return(dao.CapNhatNguoiDung(nd));
        }
        public List <clsNguoiDung_DTO> DSNguoiDung()
        {
            clsNguoiDung_DAO dao = new clsNguoiDung_DAO();

            return(dao.DanhSachNguoiDung());
        }