//检查用户名和密码
        public JsonResult CheckSession(string userName, string pwd)
        {
            IDictionary <string, string> rsdic = _service.FormInfo(userName, pwd);
            JsonResult json = new JsonResult();

            json.Data = new
            {
                flag     = rsdic["flag"],
                userName = rsdic["userName"],
                pwd      = rsdic["pwd"]
            };
            return(Json(json, JsonRequestBehavior.AllowGet));
        }