实体框架6：查询相关实体

Question

我很难从EF中检索正确相关的数据。这是我第一次使用代码生成数据，所以这里是我的课程（为了简洁而被剥离）

Author.cs

public class Author
{
        [Key]
        public int author_id {get;set;}
        public string author_name {get;set;}
        public string author_email {get;set;}
        public virtual ICollection<AuthorCategory> AuthorCategories {get; set;}
        public Author()
        {
            this.AuthorCategories = new HashSet<AuthorCategory>();
        }
}

AuthorCategory.cs

public class AuthorCategory
{
    [Key]
    public int category_id { get; set; }
    public string category_name { get; set; }
    public virtual ICollection<Author> Authors { get; set; }

    public AuthorCategory()
    {
        this.Authors = new HashSet<Author>();
    }
}

AuthorRelation.cs

public class AuthorCategoryRelation
{
    public AuthorCategoryRelation()
    {
        this.AuthorCategories = new HashSet<AuthorCategory>();
        this.Authors = new HashSet<Author>();

    }
    public int author_id { get; set; }
    public int category_id { get; set; }

    public ICollection<AuthorCategory> AuthorCategories { get; set; }
    public ICollection<Author> Authors { get; set; }
}

我希望检索每个作者的列表以输出作者姓名，电子邮件和每个作者所属的（可能的多个）类别，我跑;

    var authors = (from a in db.Authors
                   select new
                   {
                       first_name = a.first_name,
                       last_name = a.last_name,
                       cats = a.AuthorCategories.ToList()
                   });

我以JSON格式返回结果集。所以我期望的是一个简单的输出结果就是这样的

{
  "Authors": [
    {
      "AuthorCategories": [
        {
          "Authors": [
            {
              "AuthorCategories": [],
              "author_id": 8,
              "first_name": "Ava",
              "last_name": "Mcmillan",
              "photo_path": "C:\\Inetpub\\HwHosts\\ontayka.com\\img\\authors\\t1_ava_mcmillan.jpg",
              "photo_social_sharing": null,
              "username": "xoxywaf",
              "password": "8810160BFD79D7DE46388533E26FFD247D152514",
              "pass_guid": "7b574629-32b0-4905-b51c-4315a446e96e",
              "email": "kekozod@yahoo.com",
              "twitter": "Ut aspernatur blanditiis reprehenderit deserunt aut autem accusantium ea natus irure rerum quaerat",
              "facebook": "Voluptatem Deserunt illo in sit",
              "date_created": "2016-08-16T17:31:50.383",
              "date_last_login": null,
              "author_status": 0,
              "about_author": "Qui quis laboriosam, pariatur? In in est, sunt optio, sit, quia et.",
              "require_publish_approval": true,
              "column_name": null,
              "column_image": null,
              "change_password_at_first_login": false,
              "tenant_id": 1,
              "Posts": null
            }
          ],
          "category_id": 2,
          "category_name": "Ekonomi",
          "tenant_id": 0
        }
      ],
      "author_id": 7,
      "first_name": "Caryn",
      "last_name": "Hines",
      "photo_path": "C:\\Inetpub\\HwHosts\\ontayka.com\\img\\authors\\t1_caryn_hines.jpg",
      "photo_social_sharing": null,
      "username": "jocusadom",
      "password": "609DE1F0C08B8FC4A797E381A160A64285A3F1D8",
      "pass_guid": "324bf75b-f22e-486f-905d-45623f34a09b",
      "email": "favojyj@hotmail.com",
      "twitter": "Sed aliquid dolores veniam explicabo In proident rem sit nisi fugiat laboris nisi esse aut",
      "facebook": "Magnam dolorum voluptatem atque voluptate assumenda velit rerum ducimus itaque eos aut",
      "date_created": "2016-08-16T17:30:46.44",
      "date_last_login": null,
      "author_status": 1,
      "about_author": "Deserunt et consequatur, fuga. Dolores et fugit, exercitationem alias fugiat iusto adipisicing nemo ullam eaque harum nemo sit, dignissimos.",
      "require_publish_approval": false,
      "column_name": null,
      "column_image": null,
      "change_password_at_first_login": false,
      "tenant_id": 1,
      "Posts": null
    }
  ],
  "category_id": 1,
  "category_name": "Spor",
  "tenant_id": 0
}

显然这里肯定是错的。我非常感谢任何有经验的开发人员来指导我。我正在定义分类错误？或者是我做错了什么？

提前致谢！