Linq 异常表达式必须是 MemberExpression

发布于 2025-01-01 07:45:08 字数 525 浏览 1 评论 0原文

我正在处理 linq 查询，并尝试按照 Mutilevel 中的建议将实体包含到多级别包含在 C# Linq 中。

所以我写下一个查询，比如

 query.Include(u => u.Stops.Select(d => d.Address).Select(c => c.City));

查询在哪里

IQueryable<SomeEntity> query

，然后我得到了异常

表达式必须是 MemberExpression

我的实体的屏幕截图是在此处输入图像描述请帮忙，谢谢

原文

i am working on a linq query and try to include entities upto multi level as per suggested in Mutilevel include in C# Linq.

So i write down a query like

 query.Include(u => u.Stops.Select(d => d.Address).Select(c => c.City));

where query is

IQueryable<SomeEntity> query

and i get the exception

The expression must be a MemberExpression

Screenshot for my entities is enter image description here
Kindly help, Thanks

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似最初 2025-01-08 07:45:08

Include 的此重载（扩展？）不支持通过方法链包含。但是，它确实支持包含表达式的嵌套：

query.Include(u => u.Stops.Select(d => d.Address.City));

// this would work too:
categories.Include(u => u.SubCategories.Select(c => c.Items.Select(i => i.Manufacturer)));
// equals
categories.Include("SubCategories.Items.Manufacturer");

Select 部分仅用于访问集合类型属性项的成员。

This overload (extension?) of Include does not support inclusion through method chains. It does, however, support nesting of inclusion expressions:

query.Include(u => u.Stops.Select(d => d.Address.City));

// this would work too:
categories.Include(u => u.SubCategories.Select(c => c.Items.Select(i => i.Manufacturer)));
// equals
categories.Include("SubCategories.Items.Manufacturer");

The Select part is only for accessing members of collection type property items.

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