EF一对一无效

Question

我有一个班级用户：

[Table("User")]
public class User {

    public User() {
        BusinessNumber = new BusinessNumber();
    }

    [Key]
    [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int UserId { get; set; }
    public string Username { get; set; }

    [Required]
    public virtual BusinessNumber BusinessNumber { get; set; }

}

和商家编号：

public class BusinessNumber {

    public BusinessNumber() {
        Subscribers = new List<SubscriberNumber>();
    }

    [Key, ForeignKey("User")]
    public int UserId { get; set; }
    public string Sid { get; set; }
    public string PhoneNumber { get; set; }
    public string VenueName { get; set; }
    public virtual User User { get; set; }
    public List<SubscriberNumber> Subscribers { get; set; }

}

public class SubscriberNumber {

    public SubscriberNumber() {}

    [Key]
    public int SubscriberNumberId { get; set; }
    public string PhoneNumber { get; set; }

}

使用以下映射：

public class NumberConfiguration : EntityTypeConfiguration<BusinessNumber> {
    public NumberConfiguration() {
        HasKey(c => c.UserId);
        Property(c => c.UserId).HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);
        HasRequired(c => c.User).WithRequiredDependent(s => s.BusinessNumber);
    }
}

以下代码将产生一个新的BusinessNumber，而没有提供ID。 如果我检查数据库，我看到ID的用户1和ID为BusinessNumber 1 ，但user.BusinessNumber.Id为0。

var user = db.Users.First(s => s.Username == username);

我尝试使用Include但出现多重错误：

var user = db.Users.Include(s => s.BusinessNumber).First(s => s.Username == username);

我究竟做错了什么？

Answer 1

您确定此代码正确吗：

public User() 
{
   BusinessNumber = new BusinessNumber();
}

因为它将创建一个ID为零的新BusinessNumber ； 听起来像您遇到的问题。 我认为您首先需要将null保留null 。