//判断缓存
if (HttpRuntime.Cache["RoomClassList"] == null)
            {
                List<RoomClass_V2> obj = _dal.GetPageList();
                HttpRuntime.Cache.Insert("RoomClassList", obj, null, DateTime.Now.AddDays(1), System.Web.Caching.Cache.NoSlidingExpiration);
                return HttpRuntime.Cache["RoomClassList"];
            }
            else
            {
                return HttpRuntime.Cache["RoomClassList"];
            }