的EntityFramework贪婪加载所有的导航属性 [英] EntityFramework Eager Load all Navigation Properties

问题描述

我使用的是与DI和IOC Repository模式

I'm using the Repository pattern with DI and IoC.

我在信息库中创建一个函数：

I have created a function in my Repository:

T EagerGetById<T>(Guid id, string include) where T : class
{
    return _dbContext.Set<T>().Include(include).Find(id);
}

这将急切地在我的实体正确加载一个导航属性​​。

This will eagerly load one navigation property in my entity right.

但是，如果我的实体是这样的：

But if my entity looks like this:

public class Blog : PrimaryKey
{
    public Author Author {get;set;}
    public ICollection<Post> Posts {get;set;}
}

我该如何获得预先加载了作者和帖子？我会从字面上要做到：

How would I get eager loading for Author and Posts? Would I literally have to do:

_dbContext.Set<T>().Include("Author").Include("Posts").Find(id);

难免产生这样的功能：

inevitably producing a function like this:

T EagerGetById<T>(Guid id, string include, string include2, string include3) where T : class
{
    return _dbContext.Set<T>().Include(include).Include(include2).Include(include3).Find(id);
}

由于这将是一个通用<真低效/ code>库！

Because that would be really inefficient for a Generic Repository!

感谢

推荐答案

如果你不想使用字符串，你也可以做同样的任何N多的使用返回导航性能急于加载一个表达式包含。 （原始来源这里）

If you don't want to use strings, you can also do the same for any N number of includes by using an expression which returns the navigation properties to be eager loaded. (original source here)

public IQueryable<TEntity> GetAllIncluding(params Expression<Func<TEntity, object>>[] includeProperties) 
{
   IQueryable<TEntity> queryable = GetAll();
   foreach (Expression<Func<TEntity, object>> includeProperty in includeProperties) 
   {
      queryable = queryable.Include<TEntity, object>(includeProperty);
   }

   return queryable;
}

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