Linq to Sql 左连接查询
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1 var query = from t0 in context.ExpressSendMaster 2 join t1 in context.Supplier on t0.SupplierCode equals t1.SupplierCode 3 join t2 in context.ExpressSendPackageRule on t0.AreaId equals t2.Id into t0_join 4 from t0_t2 in t0_join.DefaultIfEmpty() 5 where t0.Id == MasterId 6 select new ExpressPackageOffLineModel 7 { 8 PackWeight = t0.Weight, 9 SupplierCode = t1.SupplierCode, 10 SupplierName = t1.Name, 11 SendDate = t0.SendDate, 12 OneselfNumber = t0.OneselfNumber, 13 Memo = t0.Memo, 14 GroupCheck = t0.AreaCode, 15 GroupName = t0_t2.NumberType == null ? "" : t0_t2.NumberType, 16 GroupId = t0_t2.Id == null ? 0 : t0_t2.Id, 17 LimitWeight = t0_t2.LimitWeight == null ? 0 : t0_t2.LimitWeight 18 }; 19 20 21 if (query.Count() <= 0) 22 { 23 model.HasError = true; 24 model.ErrorMessage = "错误提示"; 25 return false; 26 } 27 28 model.PackWeight = query.First().PackWeight; 29 model.SupplierCode = query.First().SupplierCode; 30 model.SupplierName = query.First().SupplierName; 31 model.SendDate = query.First().SendDate; 32 model.OneselfNumber = query.First().OneselfNumber; 33 model.GroupName = query.First().GroupName; 34 model.Memo = query.First().Memo; 35 model.GroupCheck = query.First().GroupCheck; 36 model.GroupId = query.First().GroupId; 37 model.LimitWeight = query.First().LimitWeight;
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