如何在实体框架6代码优先的同一表之间创建一对一的关系？

Question

下面是两个类的简单表示。

public class Person 
{ 
    [Key] 
    public int ID {get; set;} 
    public virtual ICollection<Friendship> FShip{ get; set; } 
} 

    public class Friendship 
    { 
     [Key] 
     public int ID { get; set; } 

     [ForeignKey("Friend1ID")] 
     public virtual Person Friend1{ get; set; } 
     public int Friend1ID { get; set; } 

     [ForeignKey("Friend2ID")] 
     public virtual Person Friend2{ get; set; } 
     public int Friend2ID{ get; set; } 

     public double FriendshipScrore{ get; set; } 
    } 

当表创建时，我期待每个朋友有两个外键。但是Person表还有另外一个外键。 Person_ID（这是问题）

下面是迁移代码中的相应部分。

ForeignKey("dbo.Persons", t => t.Friend1ID, cascadeDelete: true) 
.ForeignKey("dbo.Persons", t => t.Friend2ID, cascadeDelete: true) 
.ForeignKey("dbo.Persons", t => t.Person_ID) 
.Index(t => t.Friend1ID) 
.Index(t => t.Friend2ID) 
.Index(t => t.Person_ID); 

Answer 1

你也应该调整Person类明确指定链接到Friend1组和Friend2在组类Friendship：

public class Person 
    { 
     [Key] 
     public int ID {get; set;} 

     [InverseProperty("Friend1")] 
     public virtual ICollection<Friendship> FShip1{ get; set; } 

     [InverseProperty("Friend2")] 
     public virtual ICollection<Friendship> FShip2{ get; set; } 

     [NotMapped] 
     public List<Friendship> FShip{ get { 
        return FShip1.Union(FShip2).ToList(); 
      } 
     } 
    }