linq 常用语句

  自己练习的
  switch (productDataAnalysisQuery.DataType)
            {
                case 1:
                    var data = (from hp in GPEcontext.hbl_product
                                join hcim in
                                    from hci in GPEcontext.hbl_change_info
                                    where hci.LotNum == 0 && hci.ChangeData < 0
                                    && hci.CreatedTime >= beginDate && hci.CreatedTime <= endDate
                                    group hci by new { hci.ProductId } into G
                                    select new
                                    {
                                        ProductId = G.Key.ProductId,
                                        Amount = G.Sum(item => Math.Abs(item.ChangeData.Value))
                                    } on hp.id equals hcim.ProductId
                                orderby hcim.Amount descending
                                select new ProductDataAnalysisodel
                                {
                                    ProductName = hp.ProductName,
                                    ProductCode = hp.ProductCode,
                                    Amount = hcim.Amount
                                }).Take(20);
                    pageModel.Models = data.FindBy(item => true, productDataAnalysisQuery.PageNo, productDataAnalysisQuery.PageSize, out total, item => item.Amount, false);
                    break;
                case 2:
                    var data2 = (from hp in GPEcontext.hbl_product
                                 join hcim in
                                     from hci in GPEcontext.hbl_change_info
                                     where hci.LotNum == 0 && hci.ChangeData < 0
                                     && hci.CreatedTime >= beginDate && hci.CreatedTime <= endDate
                                     group hci by new { hci.ProductId } into G
                                     select new
                                     {
                                         ProductId = G.Key.ProductId,
                                         Amount = G.Sum(item => Math.Abs(item.ChangeData.Value))
                                     } on hp.id equals hcim.ProductId
                                 orderby hcim.Amount
                                 select new ProductDataAnalysisodel
                                 {
                                     ProductName = hp.ProductName,
                                     ProductCode = hp.ProductCode,
                                     Amount = hcim.Amount
                                 }).Take(20);
                    pageModel.Models = data2.FindBy(item => true, productDataAnalysisQuery.PageNo, productDataAnalysisQuery.PageSize, out total, item => item.Amount, false);
                    break;
                case 3:
                    var data3 = (from hp in GPEcontext.hbl_product
                                 join hcim in
                                     from hci in GPEcontext.hbl_change_info
                                     where hci.LotNum == 0 && hci.ChangeData < 0
                                     && hci.CreatedTime >= beginDate && hci.CreatedTime <= endDate
                                     group hci by new { hci.ProductId } into G
                                     select new
                                     {
                                         ProductId = G.Key.ProductId,
                                         Amount = G.Count()
                                     } on hp.id equals hcim.ProductId
                                 orderby hcim.Amount descending
                                 select new ProductDataAnalysisodel
                                 {
                                     ProductName = hp.ProductName,
                                     ProductCode = hp.ProductCode,
                                     Amount = hcim.Amount
                                 }).Take(20);
                    pageModel.Models = data3.FindBy(item => true, productDataAnalysisQuery.PageNo, productDataAnalysisQuery.PageSize, out total, item => item.Amount, false);

                    break;
                case 4:
                    var data4 = (from hp in GPEcontext.hbl_product
                                 join hcim in
                                     from hci in GPEcontext.hbl_change_info
                                     where hci.LotNum == 0 && hci.ChangeData < 0
                                     && hci.CreatedTime >= beginDate && hci.CreatedTime <= endDate
                                     group hci by new { hci.ProductId } into G
                                     select new
                                     {
                                         ProductId = G.Key.ProductId,
                                         Amount = G.Count()
                                     } on hp.id equals hcim.ProductId
                                 orderby hcim.Amount
                                 select new ProductDataAnalysisodel
                                 {
                                     ProductName = hp.ProductName,
                                     ProductCode = hp.ProductCode,
                                     Amount = hcim.Amount
                                 }).Take(20);
                    pageModel.Models = data4.FindBy(item => true, productDataAnalysisQuery.PageNo, productDataAnalysisQuery.PageSize, out total, item => item.Amount, false);

                    break;
                case 5:
                    var data5 = (from hp in GPEcontext.hbl_product
                                 join hs in
                                     from hps2 in GPEcontext.hbl_product_stock
                                     join p in
                                         from hps in GPEcontext.hbl_product_stock
                                         group hps by new { hps.ProductID } into G
                                         select new
                                         {
                                             ProductId = G.Key.ProductID,
                                             CreatedTime = G.Max(p => p.CreatedTime)
                                         }
                                     on new { A = hps2.ProductID, B = hps2.CreatedTime } equals new { A = p.ProductId, B = p.CreatedTime }
                                     select new
                                  {
                                      ProductId = hps2.ProductID,
                                      Amount = hps2.Stock
                                  }
                                             on hp.id equals hs.ProductId
                                 orderby hs.Amount descending
                                 select new ProductDataAnalysisodel
                                 {
                                     ProductName = hp.ProductName,
                                     ProductCode = hp.ProductCode,
                                     Amount = hs.Amount.Value
                                 }).Take(20);
                    pageModel.Models = data5.FindBy(item => true, productDataAnalysisQuery.PageNo, productDataAnalysisQuery.PageSize, out total, item => item.Amount, false);

                    break;
                case 6:
                    var data6 = (from hp in GPEcontext.hbl_product
                                 join hs in
                                     from hps2 in GPEcontext.hbl_product_stock
                                     join p in
                                         from hps in GPEcontext.hbl_product_stock
                                         group hps by new { hps.ProductID } into G
                                         select new
                                         {
                                             ProductId = G.Key.ProductID,
                                             CreatedTime = G.Max(p => p.CreatedTime)
                                         }
                                     on new { A = hps2.ProductID, B = hps2.CreatedTime } equals new { A = p.ProductId, B = p.CreatedTime }
                                     select new
                                     {
                                         ProductId = hps2.ProductID,
                                         Amount = hps2.Stock
                                     }
                                             on hp.id equals hs.ProductId
                                 orderby hs.Amount 
                                 select new ProductDataAnalysisodel
                                 {
                                     ProductName = hp.ProductName,
                                     ProductCode = hp.ProductCode,
                                     Amount = hs.Amount.Value
                                 }).Take(20);
                    pageModel.Models = data6.FindBy(item => true, productDataAnalysisQuery.PageNo, productDataAnalysisQuery.PageSize, out total, item => item.Amount, false);

                    break;
            }