在“SelectMany”的调用中，类型推断失败 [英] Type inference failed in the call to 'SelectMany'

问题描述

我有这个LINQ查询：

I have this LINQ query:

        var businessAffiliates = from b in context.Businesses
                                 from ba in b.BusinessOfficers
                                 from p in ba.Person                                     
                                 select b;

但我收到此错误：

类型
'myproj.Models.Person'的表达式不允许在查询中的后续from子句

表达式，源类型为
'System.Linq.IQueryable'。
调用
'SelectMany'时，类型推断失败。

An expression of type 'myproj.Models.Person' is not allowed in a subsequent from clause in a query expression with source type 'System.Linq.IQueryable'. Type inference failed in the call to 'SelectMany'.

推荐答案

p>它看起来像ba.Person它是单个对象，但来自子句的期望一系列对象。
如果您用 let p = ba.Person 替换该行，那么它将工作。但是我想知道为什么您需要从子句中添加额外的。

It looks like ba.Person it a single object, but the from clause expects a sequence of objects. if you replace that line with let p = ba.Person then it would work. But i wonder why you need those additional from clauses.

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