使用下面提到的查询,我得到了一个名为 PromotionValue的列的所有值。我想得到*匹配*的所有值的总和
var matched = from table1 in dvtempPropertyRoomRatePromotion.ToTable().AsEnumerable()
join table2 in dvPropertyRooms.ToTable().AsEnumerable() on
table1.Field<DateTime>("RateDate") equals table2.Field<DateTime>("RateDate")
where table1.Field<DateTime>("RateDate") == table2.Field<DateTime>("RateDate")
select table1.Field<string>("promotionValue");