后台调用存储过程

            uss.Username = username;

            uss.Userpwd = userpwd;

            SqlParameter[] pms = new SqlParameter[3];

            pms[0] = new SqlParameter("@stuname", uss.Username);

            pms[1] = new SqlParameter("@stuno", uss.Userpwd);

            pms[2] = new SqlParameter("@str", SqlDbType.VarChar, 50);

            pms[2].Direction = ParameterDirection.Output;

            SQLHelper.GetSingle("up_Login", true, pms);

            string s = pms[2].Value.ToString();   

            return s;