按年份和月份分组获得值

Question

我试图在月份和年份对实体结果进行分组而没有成功。

表格

| StoreName |年|月| OrderCount |

| Stockholm | 2014 | 1 | 28473 |

| Stockholm | 2014 | 2 | 26830 |

当前结果：

[
    {
        "storeName": "Stockholm",
        "values": [
            {
                "year": 2014,
                "month": "januari",
                "orderCount": 28473
            }
        ]
    },
    {
        "storeName": "Stockholm",
        "values": [
            {
                "year": 2014,
                "month": "februari",
                "orderCount": 26830
            }
        ]
    }
]

希望的结果

[
        {
            "storeName": "Stockholm",
            "values": [
                {
                    "year": 2014,
                    "month": "januari",
                    "orderCount": 28473
                },
                {
                    "year": 2014,
                    "month": "februari",
                    "orderCount": 26830
                }
            ]
        }
    ]

代码:(这是处理分组的代码）

public static IEnumerable<MonthlyOrdersByStoreResponse> ToMonthlyOrdersByStore(this IEnumerable<OrderMonthlyEntity> orderMonthlyEntities)
        {
            return from order in orderMonthlyEntities
                   group order by new { order.StoreName, order.Month } into grouping
                   select
                       new MonthlyOrdersByStoreResponse()
                       {
                           StoreName = grouping.Key.StoreName,
                           Values = (from q in grouping
                                     select
                                     new OrderDeliveryCountByMonth()
                                     {
                                         Year = q.Year,
                                         Month = new DateTime(q.Year, q.Month, 1).ToMonthName(),
                                         OrderCount = q.OrderCount,
                                     }).ToList()
                       };
        }

Answer 1

解决了此代码的问题：

public static IEnumerable<MonthlyOrdersByStoreResponse> ToMonthlyOrdersByStore(this IEnumerable<OrderMonthlyEntity> orderMonthlyEntities)
        {
            return from order in orderMonthlyEntities
                   group order by new { order.StoreName } into grouping
                   select
                       new MonthlyOrdersByStoreResponse()
                       {
                           StoreName = grouping.Key.StoreName,
                           Values = (from q in grouping
                                     select
                                     new OrderDeliveryCountByMonth()
                                     {
                                         Year = q.Year,
                                         Month = new DateTime(q.Year, q.Month, 1).ToMonthName(),
                                         OrderCount = q.OrderCount,
                                     }).ToList()
                       };
        }

Answer 2

您希望结果按StoreName分组，然后按Year, Month分组：

return 
    from item in orderMonthlyEntities
    group item by item.StoreName into storeNameGroup
    orderby storeNameGroup.Key
    select new MonthlyOrdersByStoreResponse
    {
        StoreName = storeNameGroup.Key,
        Values = 
            (from item in storeNameGroup
             group item by new { item.Year, item.Month } into monthGroup
             orderby monthGroup.Key.Year, monthGroup.Key.Month
             select new OrderDeliveryCountByMonth
             {
                 Year = monthGroup.Key.Year,
                 Month = new DateTime(monthGroup.Key.Year, monthGroup.Key.Month, 1).ToMonthName(),
                 OrderCount = monthGroup.Sum(item => item.OrderCount)
             }).ToList()
    };