C# Datatable group by 查询

 操作Datatable  group by  查询

                //获取统计图形数据
                var dicleft = new Dictionary<string, DataTable>();
                var query = from t in dataTableList[0].AsEnumerable()
                            group t by new { mname = t.Field<string>("COL_MATERIAL_NAME") } into m
                            select new
                            {
                                MaterialName = m.Key.mname,
                                value = m.ToList()
                            };
                foreach (var item in query)
                {
                    var dtmax = new DataTable();
                    dtmax.Columns.Add("XValue");
                    dtmax.Columns.Add("YValue");
                    var dtmin = dtmax.Copy();
                    var dtavg = dtmax.Copy();
                    var dtup = dtmax.Copy();
                    var dtdown = dtmax.Copy();

                    foreach (DataRow dritem in item.value)
                    {
                        DataRow dr = dtmax.NewRow();
                        dr["XValue"] = dritem["COL_DATEMONTH"];
                        dr["YValue"] = dritem["COL_MAXVALUE"];
                        dtmax.Rows.Add(dr);
                        dr = dtmin.NewRow();
                        dr["XValue"] = dritem["COL_DATEMONTH"];
                        dr["YValue"] = dritem["COL_MINVALUE"];
                        dtmin.Rows.Add(dr);
                        dr = dtavg.NewRow();
                        dr["XValue"] = dritem["COL_DATEMONTH"];
                        dr["YValue"] = dritem["COL_AVGVALUE"];
                        dtavg.Rows.Add(dr);
                        dr = dtup.NewRow();
                        dr["XValue"] = dritem["COL_DATEMONTH"];
                        dr["YValue"] = dritem["COL_UPVALUE"];
                        dtup.Rows.Add(dr);
                        dr = dtdown.NewRow();
                        dr["XValue"] = dritem["COL_DATEMONTH"];
                        dr["YValue"] = dritem["COL_DOWNVALUE"];
                        dtdown.Rows.Add(dr);
                    }
                    dicleft.Add(item.MaterialName + "-最高值", dtmax);
                    dicleft.Add(item.MaterialName + "-最低值", dtmin);
                    dicleft.Add(item.MaterialName + "-平均值", dtavg);
                    dicleft.Add(item.MaterialName + "-内控上限", dtup);
                    dicleft.Add(item.MaterialName + "-内控下限", dtdown);
                }
                chartEntity = QMBasicData.AnalyticSeriesData(dicleft, "", new Dictionary<string, DataTable>(), "",
                    ChartTypeEnum.Line);