public IPagedList <TrackingNumberDetailInfo> GetTrackingNumberPagedList(int page, int pageSize, string trackingNumberID) { Expression <Func <TrackingNumberDetailInfo, bool> > filter = p => true; filter = filter.AndIf(p => p.TrackingNumberID == trackingNumberID, !string.IsNullOrWhiteSpace(trackingNumberID)); Func <IQueryable <TrackingNumberDetailInfo>, IOrderedQueryable <TrackingNumberDetailInfo> > orderBy = o => o.OrderByDescending(p => p.WayBillNumber); return(_trackingNumberDetailInfoRepository.FindPagedList(page, pageSize, filter, orderBy)); }