Linq取得按某列编组中最大值的行，group by,groupby,Max

        var NewistRows = from ff in LinkToSQL.JobNumberList
                         from gg in LinkToSQL.M1_Test
                         let tt = (
                         from g in LinkToSQL.M1_Test
                         group g by g.PartNumber into ss
                         select new { ss.Key, max = ss.Max(p => p.Times) }
                         )
                         from t in tt
                         where ff.jobNumber == messages[1].ToString() &&
                         ff.isDelete == false &&
                         ff.jobNumberID == gg.FK_JobNumber &&
                         gg.PartNumber == t.Key &&
                         gg.Times == t.max
                         select gg;