在Subsonic 3中左加入 [英] Left Join in Subsonic 3

问题描述

我正在尝试使用linq在亚音速3中进行左联接，但似乎不起作用，我遇到了一个大错误.

I'm trying to do a left join in subsonic 3 using linq but it doesn't seem to work, I get a big error.

        var post = from p in Post.All()
                    join q in Quote.All() on p.ID equals q.PostID into pq
                    where p.ID == id.Value
                    from qt in pq.DefaultIfEmpty()
                    select new {p, qt};

我正在使用Rob的最新GIT版本亚音速3，但尝试左连接时出现错误，请参见下文. 我已经搜索过，但是没有找到任何解决方案.

I'm using subsonic 3, latest GIT version from Rob, but I'm getting an error, see below, when I try a left join. I have searched but I didn't found any solution.

谁能向我解释错误的原因以及如何解决? 谢谢

Can anyone explain to me why the error and how to fix it? Thanks

Expression of type 'System.Collections.Generic.IEnumerable1[GetAQuote.Post]' cannot be used for parameter of type 'System.Linq.IQueryable1[GetAQuote.Post]' of method 'System.Linq.IQueryable1[<>f__AnonymousType221[GetAQuote.Post], System.Collections.Generic.IEnumerable1%5BGetAQuote.Quote%5D, System.Linq.Expressions.Expression1[System.Func2%5BGetAQuote.Post,System.Int32%5D%5D, System.Linq.Expressions.Expression1[System.Func2%5BGetAQuote.Quote,System.Int32%5D%5D, System.Linq.Expressions.Expression1[System.Func3%5BGetAQuote.Post,System.Collections.Generic.IEnumerable1[GetAQuote.Quote],<>f__AnonymousType22%5BGetAQuote.Post,System.Collections.Generic.IEnumerable 1％5BGetAQuote.Quote％5D％5D％5D％5D> GetAQuote.Post，System.Collections.Generic.IEnumerable1 [GetAQuote.Quote]]] GroupJoin [Post，Quote，Int32，<> f__AnonymousType22'`

Expression of type 'System.Collections.Generic.IEnumerable1[GetAQuote.Post]' cannot be used for parameter of type 'System.Linq.IQueryable1[GetAQuote.Post]' of method 'System.Linq.IQueryable1[<>f__AnonymousType221[GetAQuote.Post], System.Collections.Generic.IEnumerable1%5BGetAQuote.Quote%5D, System.Linq.Expressions.Expression1[System.Func2%5BGetAQuote.Post,System.Int32%5D%5D, System.Linq.Expressions.Expression1[System.Func2%5BGetAQuote.Quote,System.Int32%5D%5D, System.Linq.Expressions.Expression1[System.Func3%5BGetAQuote.Post,System.Collections.Generic.IEnumerable1[GetAQuote.Quote],<>f__AnonymousType22%5BGetAQuote.Post,System.Collections.Generic.IEnumerable1%5BGetAQuote.Quote%5D%5D%5D%5D">GetAQuote.Post,System.Collections.Generic.IEnumerable1[GetAQuote.Quote]]] GroupJoin[Post,Quote,Int32,<>f__AnonymousType22'`

推荐答案

要解决Subsonic3中的Left Join，您只需要在linq查询中设置.AsEnumerable()方法即可.

to solve Left Join in Subsonic3 you just need to set .AsEnumerable() method on your linq query.

尝试一下

categories.AsEnumerable()或products.AsEnumerable()

categories.AsEnumerable() or products.AsEnumerable()

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