asp.net-mvc – 实体框架核心可空外键

型号：

public class Company
{
    [Key]
    [Required]
    public int Id { get; set; }
    [Display(Name = "Company Name")]
    public string CompanyName { get; set; }
    [Display(Name = "Main Phone")]
    public string LandPhone { get; set; }
    [Display(Name = "Fax")]
    public string FaxPhone { get; set; }
}

public class Contact
{
    [Key]
    [Required]
    public int Id { get; set; }
    [Display(Name ="First Name")]
    public string FirstName { get; set; }
    [Display(Name = "Last Name")]
    public string LastName { get; set; }
    [EmailAddress]
    public string Email { get; set; }
    [Display(Name = "Mobile Phone")]
    public string MobilePhone { get; set; }
    [Display(Name = "Office Phone")]
    public string LandPhone { get; set; }
    [Display(Name = "Fax")]
    public string FaxPhone { get; set; }
    public string Title { get; set; }
    public int CompanyId { get; set; }
    [ForeignKey("CompanyId")]
    public Company Company { get; set; }
}

当我尝试获取所有联系人的列表,并且其中一个联系人在我的数据库中具有CompanyId的空值时,它将在它返回的列表中跳过该联系人.例如,查询var contacts = _context.Contacts.Include(c => c.Company).ToList();只返回下表中的Josh Stone：

Contacts Table

我正在使用Entity Framework Core 1.0.0.任何帮助将是真诚的感谢.