用户代码错误未处理DbUpdateException

Question

给出的错误代码非常模糊，所以我很难跟踪错误。我只是假设它与我如何关联我的桌子有关？

错误代码是：

{"The INSERT statement conflicted with the FOREIGN KEY constraint \"FK_dbo.LGMembers_dbo.Lifegroups_LifegroupID\". 
The conflict occurred in database \"aspnet-COGSimple-20140204091131\", table \"dbo.Lifegroups\", column 'LifegroupID'.\r\nThe statement has been terminated."}

从这篇文章INSERT statement conflicted with the FOREIGN KEY constraint，它说：

  

FK的工作方式是它不能在该列中具有不在引用表的主键列中的值

但是，我的表格是以每个fk链接到主键的方式引用的。

受影响的表格：

public class Lifegroup
{
    [Key]
    public int LifegroupID { get; set; }
    [Display(Name = "Lifegroup Name")]
    public string LGName { get; set; }
    [Display(Name = "Lifegroup Type")]
    public string LGType { get; set; }
    public DateTime DateCreated { get; set; }

    public int LGLeaderID { get; set; }

    [ForeignKey("LGLeaderID")]
    public virtual LGLeader LGLeader { get; set; }
}

public class LGLeader
{
    [Key]
    public int LGLeaderID { get; set; }

    public string UserID { get; set; }

    [ForeignKey("UserID")]
    public virtual User User { get; set; }
}

public class LGMember
{
    [Key]
    public int LGMemberID { get; set; }

    public string UserID { get; set; }
    public int LifegroupID { get; set; }

    [ForeignKey("UserID")]
    public virtual User User { get; set; }
    [ForeignKey("LifegroupID")]
    public virtual Lifegroup Lifegroup { get; set; }
}

非常感谢！

修改：

尝试向LGMember插入数据时，错误来自 db.SaveChanges（）。