关于C#：如何将此SQL请求转换为Lambda表达式或LINQ

How to convert this sql request to Lambda expression or LINQ

如何将以下查询转换为lambda表达式或LINQ？

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SELECT * FROM PrelevementClient as pc
LEFT JOIN ContratIBAN AS ci ON ci.IDCMPT = pc.IDCMPT
LEFT JOIN Contrat AS ctr ON ctr.NOCONTRAT = ci.NOCONTRAT
WHERE pc.IDPRELEVEMENT = '111'
AND DTPROCHAINPREL >= getdate()

困难之处在于有两个左连接。

相关讨论

每个" join"之后都有一个" from"。

在请求的末尾将所有" from"分组会产生问题。

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DateTime date = DateTime.Now.AddMonths(1);
var prelevements = from pc in set.Where(s => s.DTPROCHAINPREL >= DateTime.Today && s.NOSOC == nosoc && s.DTPROCHAINPREL < date)
join ci in context.Set<ContratIBAN>().Where( g => g.PRELEVEMENTBCA == true) on pc.IDCMPT equals ci.IDCMPT into cileft
from ci in cileft.DefaultIfEmpty()
join co in context.Set<Contrat>() on ci.NOCONTRAT equals co.NOCONTRAT into coleft
from co in coleft.DefaultIfEmpty()

希望有帮助：

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var query = from pc in Context.PrelevementClient
join ci in Context.ContratIBAN on pc.IDCMPT equals ci.IDCMPT into ciLeft
from ci in ciLeft.DefaultIfEmpty()
join co in Context.Contrat on ci.nocontrat equals co.nocontrat into coLeft
from co in coLeft.DefaultIfEmpty()
where pc.idprelevement =="111" && pc.dtprochainprel >= DateTime.Today
select new
{
//bind what you want
// and dont forget to manage if co||ci.property is null...
}