EF Code First - Include（x => x.Properties.Entity）a 1：许多关联 [英] EF Code First - Include(x => x.Properties.Entity) a 1 : Many association

问题描述

给定一个EF-Code First CTP5实体布局，如：

  public class Person {...} 
  

其中包含以下集合：

public class Address {...}

其中有一个关联：

public class Mailbox {...}

我想做：

PersonQuery.Include（x => x.Addresses）.Include（Addresses.Mailbox）

不使用魔术字符串。我想使用lambda表达式来执行。

我知道我上面输入的内容将会编译，并会将所有符合搜索条件的人员的地址和每个地址邮箱渴望加载，但它是一个令我恼火的字符串。

如果没有字符串，我该怎么办？

谢谢Stack！

解决方案

为此，您可以使用选择方法：

  PersonQuery.Include（x => x.Addresses.Select（a => a.Mailbox））; 
  

您可以在 这里 和 这里 。

Given a EF-Code First CTP5 entity layout like:

public class Person { ... }

which has a collection of:

public class Address { ... }

which has a single association of:

public class Mailbox { ... }

I want to do:

PersonQuery.Include(x => x.Addresses).Include("Addresses.Mailbox")

WITHOUT using a magic string. I want to do it using a lambda expression.

I am aware what I typed above will compile and will bring back all Persons matching the search criteria with their addresses and each addresses' mailbox eager loaded, but it's in a string which irritates me.

How do I do it without a string?

Thanks Stack!

解决方案

For that you can use the Select method:

PersonQuery.Include(x => x.Addresses.Select(a => a.Mailbox));

You can find other examples in here and here.

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