//public SPListItemCollection Query(SPList list, string expr, int rowLimit , bool rec )
        //{
        //    SPListItemCollection items = null;
        //    SPSecurity.RunWithElevatedPrivileges(delegate()
        //    {
        //        using (SPSite site = new SPSite(SPContext.Current.Site.ID))
        //        {
        //            using (SPWeb web = site.OpenWeb(SPContext.Current.Web.ID))
        //            {
        //                SPList list2 = web.Lists[list.ID];
        //                SharePointService svr = new SharePointService(web);
        //                items = svr.Query(list2, expr, rowLimit, rec);
        //            }
        //        }
        //    });
        //    return items;
        //}
        public SPListItemCollection Query( SPList list , CamlExpression expr , int rowLimit , params OrderPair[] orders )
        {
            SPListItemCollection items = null;
            SPSecurity.RunWithElevatedPrivileges(delegate()
            {
                using (SPSite site = new SPSite(SPContext.Current.Site.ID))
                {
                    using (SPWeb web = site.OpenWeb(this._web.ID))
                    {
                        SPList list2 = web.Lists[list.ID];

                        SharePointService svr = new SharePointService(web);
                        items = svr.Query(list2, expr, rowLimit, orders);
                    }
                }
            });
            return items;
        }