Question

目标是拥有一个API，其中包含来自GravityZone的所有字段以及来自Zone表的区域名称。我已经尝试了以下代码的几种排列而没有成功。它目前为区域提供null，我希望将该名称作为字符串或对象的一部分。我正在使用我无法修改的现有表格。

型号：

public partial class Zone
{
    [Key]
    [Column("ZONE_ID")]
    public decimal ZoneId { get; set; }

    [Column("ZONE_CODE")]
    public decimal ZoneCode { get; set; }

    [Column("ZONE_NAME")]
    public string ZoneName { get; set; }

    public virtual ICollection<GravityZone> GravityZones { get; set; }
}

public partial class GravityZone
{
    [Key]
    [Column("GRAVITY_ID")]
    public decimal GravityZoneId { get; set; }

    [Column("ZONE_CODE")]
    public decimal ZoneCode { get; set; }

    [Column("ELEVATION")]
    public decimal Elevation { get; set; }

    [Column("REMARK")]
    [StringLength(2000)]
    public string Remark { get; set; }

    public virtual Zone Zone { get; set; }
}

上下文（仅关系部分）

modelBuilder.Entity<Zone>()
    .HasKey(e => e.ZoneCode);

modelBuilder.Entity<GravityZone>()
    .HasRequired(e => e.Zones);

除了这部分外，其他所有内容都很棒：

"Zones":null,

Answer 1

现在可以在Entity Framework 7（即EF Core 1.0）中使用。

来自.Net实体框架用户语音 Unique Constraint (i.e. Candidate Key) Support ：

EF Core 1.0中添加了对此功能的支持，我们没有计划将其添加到EF6代码库中。

Answer 2

I don't think it is possible cause it would cause a lot of trouble. Foreign key should should always point to some key of a table. I don't think you are able to tell EF about candidate keys.

Edit:

Similar Questions: Entity Framework 5.0 composite foreign key to non primary key - is it possible?

Here is answer for your question. As I thought EF does not understand the concept of uniqueness with exception of primary key.

Entity Framework foreign keys to non-primary key fields

实体框架6.1.3将外键映射到非主键

2 个答案: