Question

linq to sql 怎么样写 多个字段相等 的查询

我的意思是两张表的联合查询，如： var model = from v in dc.LimitedPriceTexts join a in dc.D_BiddingMedicineTexts on v.Category equals a.QualityLevel select v;
然后我想用多个字段相等；如：我还想 LimitedPriceTexts 表中的另外一个字段和D_BiddingMedicineTexts 的另外一个字段相等；
怎么样写呢？谢谢了

Answer 1

你是指多个查询条件么？
from n in DBContext.TableA
where n.A1== a && n.A2== b
select n

追问

我的意思是两张表的联合查询，如： var model = from v in dc.LimitedPriceTexts join a in dc.D_BiddingMedicineTexts on v.Category equals a.QualityLevel select v;
然后我想用多个字段相等；如：我还想 LimitedPriceTexts 表中的另外一个字段和D_BiddingMedicineTexts 的另外一个字段相等；
怎么样写呢？谢谢了

追答

var model = from v in dc.LimitedPriceTexts
join a in dc.D_BiddingMedicineTexts
on v.Category equals a.QualityLevel
join b in dc.D_BiddingMedicineTexts
on v.other equals b.other

ps:如果那俩表有主外键关系，根本不用join，直接可调用关系表的字段

Answer 2

var model = from v in dc.LimitedPriceTexts
join a in dc.D_BiddingMedicineTexts on v.Category equals a.QualityLevel into va
join b in dc.D_BiddingMedicineTexts on v.Other equals b.Other into vb
from q1 in va
from q2 in vb
select new{
v.others,
q1.others,
q2.others};