在HasOptional（）中映射外键。在实体框架中WithOptionalDependent（）关系6 [英] Mapping foreign key in HasOptional().WithOptionalDependent() relation in Entity Framework 6

问题描述

我在Entity Framework 6.1.3中有以下数据模型：

I have the following data-model in Entity Framework 6.1.3:

using System.Data.Entity;

public class Student
{
    public int Id { get; set; }
    public virtual Contact Contact { get; set; }
}

public class Contact
{
    public int Id { get; set; }
    public virtual Student Student { get; set; }
}

public class MyContext : DbContext
{
    protected override void OnModelCreating(DbModelBuilder builder)
    {
        builder.Entity<Contact>()
            .HasOptional(x => x.Student)
            .WithOptionalDependent(x => x.Contact)
            .WillCascadeOnDelete(true);
    }
}

public static class Program
{
    private static void Main()
    {
        Database.SetInitializer(new DropCreateDatabaseAlways<MyContext>());

        using (var context = new MyContext())
            context.Database.Initialize(force: true);
    }
}

当我启动这段代码时，我得到了正确的表结构我的目标是：

When I launch this code, I get exactly the right table structure I am aiming for:

dbo.Contacts
    Id (PK)
    Student_Id (FK, NULL, CASCADE ON DELETE)

dbo.Students
    Id (PK)

但是，现在我想在联系人实体中添加 Student_Id 属性。所以我可以阅读 Student_Id ，而无需通过 .Student.Id 导航加入其他表。

However, now I would like to add the Student_Id property to be available in the Contact entity. So I can read the Student_Id without needing to join the other table through .Student.Id navigation.

如果我将属性添加到联系人实体中，我可以使用两列 Student_Id 和 Student_Id1 ，或者我最后会出现一条错误消息，说类型中的每个属性名称必须是唯一的。。

If I add the property to the Contact entity, I end up either with two columns Student_Id and Student_Id1, or I end up with an error message saying Each property name in a type must be unique..

列已经在数据库中，我需要的只是在实体中拥有它，为什么这么麻烦？有没有一个解决方案？

The column is already in the database, all I need is to have it in the entity as well, why is it so much trouble? Is there a solution?

推荐答案

我设法在询问GitHub 。

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