Question

例如，我有以下销售人员名单，以及两项关键绩效指标（KPI）的得分：

SalesmanID    KPI1    KPI2
Alice          20       4
Betty          50       6
Cindy          40       8
Doris          70       2
Emily          30       3

首先，我们按照KPI1按降序排列销售人员，如下所示。

SalesmanID    KPI1    KPI1_Rank 
Doris          70        1
Betty          50        2
Cindy          40        3
Emily          30        4
Alice          20        5

接下来，我们按照KPI2按降序排列销售人员，如下所示。

SalesmanID    KPI2   KPI2_Rank
Cindy          8        1
Betty          6        2
Alice          4        3
Emily          3        4
Doris          2        5

最后，我们将它们放在一起计算Overall_Rank作为KPI1_Rank和KPI2_Rank的平均值（即Overall_Score =（KPI1_Rank + KPI2_Rank）/ 2）

SalesmanID    KPI1_Rank    KPI2_Rank    Overall_Score
Alice            5            3             4
Betty            2            2             2
Cindy            3            1             2
Doris            1            5             6
Emily            4            4             4

然后我们按照Overall_Score的降序对销售人员进行排名。

SalesmanID    Overall_Score   Overall_Rank
Doris          6                 1
Alice          4                 2 (Tie)
Emily          4                 2 (Tie)
Cindy          2                 4 (Tie)
Betty          2                 4 (Tie)

使用C＃LINQ可以实现这一点吗？

Answer 1

长代码，但它用于教育目的。

using System.Linq;

namespace ConsoleApplication
{
    class Program
    {
        static void Main (string[] args)
        {
            var salesmanList = new Salesman[]
            {
                new Salesman ("Betty", 50, 6),
                new Salesman ("Cindy", 40, 8),
                new Salesman ("Doris", 70, 2),
                new Salesman ("Emily", 30, 3),
            };


            var rankByKPI1 = salesmanList.OrderByDescending (x => x.KPI1)
                                         .Select ((x, index) => new SalesmanKpiRank (x, index + 1))
                                         .ToArray (); // for debugging only

            var rankByKPI2 = salesmanList.OrderByDescending (x => x.KPI2)
                                         .Select ((x, index) => new SalesmanKpiRank (x, index + 1))
                                         .ToArray (); // for debugging only


            var overallScoreQuery = from salesman in salesmanList

                                    let  kpi1rank = rankByKPI1.Single (x => x.Salesman.Equals (salesman)).Rank
                                    let  kpi2rank = rankByKPI2.Single (x => x.Salesman.Equals (salesman)).Rank

                                    select new SalesmanOverallScore (salesman, kpi1rank, kpi2rank);


            var rankByOverallScore = overallScoreQuery.OrderByDescending (x => x.Score)
                                                      .Select ((x , index) => new { SalesmanOverallScore = x, OverallRank = index + 1});

            var result = rankByOverallScore.ToArray ();               
        }
    }


    class Salesman
    {
        public Salesman (string id, int kpi1, int kpi2)
        {
            ID   = id;
            KPI1 = kpi1;
            KPI2 = kpi2;
        }

        public string ID   { get; }
        public int    KPI1 { get; }
        public int    KPI2 { get; }

        public override bool Equals (object obj) =>ID == ((Salesman) obj).ID; // put some logic here

        public override string ToString () => $"{ID} KPI1 = {KPI1}, KPI2 = {KPI2}";
    }


    class SalesmanKpiRank
    {
        public SalesmanKpiRank (Salesman salesman, int rank)
        {
            Salesman = salesman;
            Rank     = rank;
        }

        public Salesman Salesman { get; }
        public int      Rank     { get; }

        public override string ToString () => $"{Salesman} KPI Rank = {Rank}"; // kpi1 or kpi2
    }


    class SalesmanOverallScore
    {
        public SalesmanOverallScore (Salesman salesman, int kpi1rank, int kpi2rank)
        {
            Salesman = salesman;
            KPI1Rank = kpi1rank;
            KPI2Rank = kpi2rank;
        }

        public Salesman Salesman { get; }
        public int      KPI1Rank { get; }
        public int      KPI2Rank { get; }

        public double Score => (KPI1Rank + KPI2Rank) / 2d;

        public override string ToString () => $"{Salesman.ID} {Score}";
    }
}

C＃LINQ - 排名多个标准

1 个答案: