Linq分组取分组中的最大值，并且拿到最大值对应的id

Linq分组取分组中的最大值，并且拿到最大值对应的id

            List<PhoneCallCTIPushData> phoneCallCTIPushDatas = new List<PhoneCallCTIPushData>();

            PhoneCallCTIPushData phoneCallCTIPushData1 = new PhoneCallCTIPushData() { };
            phoneCallCTIPushData1.Id = 119;
            phoneCallCTIPushData1.MobilePhoneNum = "13059310001";
            phoneCallCTIPushData1.CreateDate = Convert.ToDateTime("2022-10-01");
            phoneCallCTIPushDatas.Add(phoneCallCTIPushData1);

            PhoneCallCTIPushData phoneCallCTIPushData2 = new PhoneCallCTIPushData() { };
            phoneCallCTIPushData2.Id = 1299;
            phoneCallCTIPushData2.MobilePhoneNum = "13059310001";
            phoneCallCTIPushData2.CreateDate = Convert.ToDateTime("2022-11-02");
            phoneCallCTIPushDatas.Add(phoneCallCTIPushData2);

            PhoneCallCTIPushData phoneCallCTIPushData13 = new PhoneCallCTIPushData() { };
            phoneCallCTIPushData13.Id = 99;
            phoneCallCTIPushData13.MobilePhoneNum = "13059310001";
            phoneCallCTIPushData13.CreateDate = Convert.ToDateTime("2022-12-02");
            phoneCallCTIPushDatas.Add(phoneCallCTIPushData13);

            PhoneCallCTIPushData phoneCallCTIPushData3 = new PhoneCallCTIPushData() { };
            phoneCallCTIPushData3.Id = 3;
            phoneCallCTIPushData3.MobilePhoneNum = "13059310002";
            phoneCallCTIPushData3.CreateDate = Convert.ToDateTime("2022-10-03");
            phoneCallCTIPushDatas.Add(phoneCallCTIPushData3);

            PhoneCallCTIPushData phoneCallCTIPushData4 = new PhoneCallCTIPushData() { };
            phoneCallCTIPushData4.Id = 4;
            phoneCallCTIPushData4.MobilePhoneNum = "13059310002";
            phoneCallCTIPushData4.CreateDate = Convert.ToDateTime("2022-10-04");
            phoneCallCTIPushDatas.Add(phoneCallCTIPushData4);

            //第一轮筛选：筛选出最新日期的手机号对应的数据
            var linqResult = from t1 in phoneCallCTIPushDatas
                             group t1 by t1.MobilePhoneNum into groupTable
                             select new
                             {
                                 CreateDate2 = groupTable.Max(x => x.CreateDate),
                                 MobilePhoneNum2 = groupTable.Key
                             };

            List<PhoneCallCTIPushData> phoneCallCTIPushDatas2 = new List<PhoneCallCTIPushData>();
            Console.WriteLine("打印准备要筛选的：");
            foreach (var item in linqResult)
            {
                //第二轮筛选：匹配最新日期的手机号对应的id值
                PhoneCallCTIPushData phoneCallCTIPushData = phoneCallCTIPushDatas.Where(aa => aa.CreateDate == item.CreateDate2 && aa.MobilePhoneNum == item.MobilePhoneNum2).FirstOrDefault();
                phoneCallCTIPushDatas2.Add(phoneCallCTIPushData);
                Console.WriteLine(item.CreateDate2 + " " + item.MobilePhoneNum2 + " ");
            }
            Console.WriteLine();
            Console.WriteLine("打印结果：");
            foreach (var item in phoneCallCTIPushDatas2)
            {
                Console.WriteLine(item.Id + " " + item.MobilePhoneNum + " " + item.CreateDate);
            }
            Console.ReadKey();

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