集合的EF核心收集负载.. [英] EF Core Collection Load .. of a Collection

问题描述

使用EF Core 1.1.0

Using EF Core 1.1.0

我有一个模型，该模型具有的集合本身也具有集合.

I have a model that has collections that themselves have collections.

public class A {  
  public string Ay {get;set;}    
  public List<B> Bees {get;set;}
}

public class B {
  public string Be {get;set;}
  public List<C> Seas {get;set;}
}

public class C {
  public string See {get;set;}
  public bool InDark {get;set;}
  public List<D> Sigh {get;set;}
}

现在.. A很大，而且99％的时间我不在乎B，因此它不会被加载.如果我确实加载了它，那么它将是这样的:

Now.. A is huge, and 99% of the time I don't care about B, so it doesn't get loaded. If I did load it, then it would be something like:

context.A.Include(a=>a.Bees).ThenInclude(b=>b.Seas).ThenInclude(c=>c.Sigh)...

现在假设我已经加载了A ，而1％的发生让我关心B.我们还没有延迟加载，但是最新版本确实为我们提供了显式加载.很棒.

Now let's say I already have A loaded up and the 1% happens for me to care about B. We don't have lazy loading yet, but the last release did give us explicit loading. Awesome.

context.Entry(A).Collection(a=>a.Bees).Load();

问题似乎是没有办法在B内包含其他集合吗?除了将.Include.ThenInclude.ThenInclude.Etc重新加载A之外，我别无选择吗?

Problem seems to be that there isn't a way to include the additional collections inside B? Do I have no choice but to reload A with the .Include.ThenInclude.ThenInclude.Etc?

推荐答案

幸运的是，您可以选择.可以直接使用 Query 方法，并根据需要应用尽可能多的 Include / ThenInclude ，而不是直接调用 Load .

Fortunately you have an option. Instead of directly calling Load, you can use Query method and apply as many Include / ThenInclude as you wish.

对于您的示例，应该是这样的:

For your sample, it would be something like this:

context.Entry(A).Collection(a => a.Bees)
    .Query()
    .Include(b => b.Seas).ThenInclude(c => c.Sigh)...
    .Load();

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