首先使用流利的API在EF代码中一对一定义 [英] Define one-to-one in EF code first with fluent API

问题描述

我有两个拳头POCO（被任命者和案件）：

I have two code fist POCOs (Appointee and Case):

public class Appointee
{
    public int ID { get; set; }
    public string ProfileID { get; set; }
    public int? CaseID { get; set; }
    public string FistName { get; set; }
    public string LastName { get; set; }
    public DateTime Dob { get; set; }
    public string Ssn { get; set; }
    public string GrantNumber { get; set; }

    public virtual Case Case { get; set; }
} 

public class Case
{
    [Key]
    public int CaseID { get; set; }
    public string ProfileID { get; set; }
    public int PSCStatusID { get; set; }

    public virtual Appointee Appointee { get; set; }
}  

在我们的术语中，被任命者是个人资料的同义词。因此，我们被任命者的[Key]是ProfileID。

In our terminology Appointee is synonymous with Profile. So the [Key] of our Appointee is ProfileID.

被任命者不必分配个案，因此我将CaseID设置为可为null的int？

An appointee doesn't have to have a case assigned so I have CaseID set as nullable int - int?.

由此我得到了一个错误，例如，无法在Case和被任命者之间确定EndPoint。

From this I get the error, something like, EndPoint cannot be determined between Case and Appointee.

I认为问题出在凯斯。
ProfileID（约会对象的外键）应该是虚拟约会对象属性的导航属性。
但是我不认为它能理解导航道具不是AppointeeID，而是ProfileID。

I think the problem is in Case. ProfileID, the foreign key to Appointee, is supposed to be the navigation property for the Virtual Appointee Property. But I don't think it understands that the navigation prop is not AppointeeID but is ProfileID instead.

所以我将其放在DbContext中：

So I put this in the DbContext:

protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);
        modelBuilder.Entity<Appointee>().HasKey(a => a.ProfileID);
        modelBuilder.Entity<Case>().HasKey(c => c.CaseID);
        modelBuilder.Entity<Case>().HasRequired(c => c.Appointee);
        modelBuilder.Entity<Appointee>().HasOptional(a => a.Case);
    }

现在我得到：无效的列名'Appointee_ProfileID'。

Now I get: Invalid column name 'Appointee_ProfileID'.

如何正确设置它。

推荐答案

最后解决了这个问题。
这里有几件事。
我习惯于使用AutoInc设置代理主键，因此我为被任命者和案例设置了自动收入ID。

Finally solved this. A couple of things here. I'm so used to setting up Surrogate Primary Keys with AutoInc that I set up autoinc IDs for Appointee and Case.

确实，被任命者的密钥应为

Really the Key for Appointee should be ProfileID.

接下来，在Entity Framework中，从属表中的外键必须与父表中的主键相同，EF将其称为

Next, in Entity Framework, a Foreign key in the dependent table has to be the same as the Primary Key in the parent table, which EF refers to as the principle.

因此，一旦我意识到我的密钥既是PK又是FK，必须是ProfileID，我就进行了以下修复。

So once I got it in my head that my keys are both, PK and FK, going to have to be ProfileID, I made the following fixes.

public class Appointee
{
    [Key]
    public string ProfileID { get; set; }
    public string FistName { get; set; }
    public string LastName { get; set; }
    public DateTime Dob { get; set; }
    public string Ssn { get; set; }
    public string GrantNumber { get; set; }

    public virtual Case Case { get; set; }
}

public class Case
{
    [Key, ForeignKey("Appointee")]
    public string ProfileID { get; set; }
    public int PSCStatusID { get; set; }

    [ForeignKey("ProfileID")]
    public virtual Appointee Appointee { get; set; }
}

请注意Case的[Key，ForeignKey（ Appointee）]属性我需要告诉EF任命人是原则。

Notice the [Key, ForeignKey("Appointee")] attribute on Case which I need to tell EF that Appointee is the principle.

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