13.01.17 C#Linqクエリの最新レコード

                var wcs = ( from wc in db.WorkConditions
                          where wc.RTU_ID == e.CoverdItem.PointName
                          orderby wc.time descending
                            select (wc)).AsEnumerable().First();

                var wr1 = (from wr in db.WaterRatios
                           where wr.RTU_ID == e.CoverdItem.PointName & wr.Ch==1
                           orderby wr.time
                           select (wr.WR)).AsEnumerable().Last();
                var wr2 = (from wr in db.WaterRatios
                            where wr.RTU_ID == e.CoverdItem.PointName & wr.Ch == 2
                            orderby wr.time
                            select (wr.WR)).AsEnumerable().Last();

                mapControl1.ShowToolTip(e.CoverdItem.PointName, ""+
                    "     1：" + (wr1 / 10.0).ToString() + "%\r
" +
                    "     2：" + (wr2 / 10.0).ToString() + "%\r
" +
                    "  ："+(wcs.Voltage/10.0).ToString() +"V\r
" +
                    "  ："+wcs.Temperature.ToString() +"℃\r
" +
                    "GPRS    ："+wcs.si_0.ToString() +"\r
" );

注意:
                var wcs = ( from wc in db.WorkConditions                           where wc.RTU_ID == e.CoverdItem.PointName                           orderby wc.time descending                             select (wc)).AsEnumerable().First();                 var wr1 = (from wr in db.WaterRatios                            where wr.RTU_ID == e.CoverdItem.PointName & wr.Ch==1                            orderby wr.time                            select (wr.WR)).AsEnumerable().Last();                 var wr2 = (from wr in db.WaterRatios                             where wr.RTU_ID == e.CoverdItem.PointName & wr.Ch == 2                             orderby wr.time                             select (wr.WR)).AsEnumerable().Last();                 mapControl1.ShowTooltip(e.CoverdItem.PointName,"+"土壌含水率1:"+(wr 1/10.0).ToString()+"%r"+"土壌含水率2:"+(wr 2/10.0).ToString()+"%r"+"電圧:"+(wcs.Voltage/10.0).ToString()+"Vr"+"温度:"+wcs.Temperature.ToString()+"℃r"+"GPRS信号強度:"+wcs.si_0.ToString() +"\r");