如何将ERD转换为Code First类？

Question

我具有以下ERD，并希望将其转换为EF 4.1 Code First类。为了简单起见，我将仅关注前两个实体。

作者>引用。

这是为我的实体提供代码的正确方法，this：

public class Quote
{
    public int Id { get; set; }
    [Required, MaxLength(500)]
    public string Body { get; set; }
    public int Likes { get; set; }
    [Required]
    public bool isApproved { get; set; }
    [Required]
    public DateTime CreatedOn { get; set; }
    public int AuthorId { get; set; }
    public int LanguageId { get; set; }
    public virtual ICollection<Tag> Tags { get; set; }
}

public class Author
{
    public int Id { get; set; }
    [Required, MaxLength(30), MinLength(2)]
    public string FirstName { get; set; }
    [Required, MaxLength(30), MinLength(2)]
    public string LastName { get; set; }
    [Required]
    public DateTime DOB { get; set; }
    public DateTime DOD { get; set; }
    [Required, MaxLength(60), MinLength(2)]
    public string Occupation { get; set; }
    [Required, MaxLength(170), MinLength(5)]
    public string WikiLink { get; set; }
    public byte[] Image { get; set; }
    [Required]
    public bool isApproved { get; set; }
    [Required]
    public DateTime CreatedOn { get; set; }
    public virtual ICollection<Quote> Quotes { get; set; }
}

在为每个Quote赋予了一个Integer类型的属性的地方，它表示作者和语言的ID 或此：

public class Quote
{
    public int Id { get; set; }
    [Required, MaxLength(500)]
    public string Body { get; set; }
    public int Likes { get; set; }
    [Required]
    public bool isApproved { get; set; }
    [Required]
    public DateTime CreatedOn { get; set; }
    public Author Author { get; set; }
    public Language Language { get; set; }
    public virtual ICollection<Tag> Tags { get; set; }
}

public class Author
{
    public int Id { get; set; }
    [Required, MaxLength(30), MinLength(2)]
    public string FirstName { get; set; }
    [Required, MaxLength(30), MinLength(2)]
    public string LastName { get; set; }
    [Required]
    public DateTime DOB { get; set; }
    public DateTime DOD { get; set; }
    [Required, MaxLength(60), MinLength(2)]
    public string Occupation { get; set; }
    [Required, MaxLength(170), MinLength(5)]
    public string WikiLink { get; set; }
    public byte[] Image { get; set; }
    [Required]
    public bool isApproved { get; set; }
    [Required]
    public DateTime CreatedOn { get; set; }
    public virtual ICollection<Quote> Quotes { get; set; }
}

每个报价都具有类型作者的属性和类型语言的属性。

Answer 1

第一个例子很罕见。您在不使用导航属性的情况下公开外部属性=您在公开数据库的特定功能，但不使用面向对象的功能。

第二个例子很常见，甚至还有第三种可能的方式，使Quote实体同时具有FK和导航属性。这将使difference between independent and foreign key associations。