C# 通过实体框架5将复杂模型保存到数据库

给出以下代码，我试图将复杂对象保存到数据库中。如果我取出地址的引用，基本机构会正确保存，但添加地址后，我会得到外键错误，并且不会保存任何内容。保存复杂类的正确方法是什么

   Institution inst = new Institution();
   inst.Name = "Institution Name";
   Address address = new Address();
   address.Street1 = "1234 west main";      
   address.City = "Gotham";
   address.State = "WI";
   address.PostalCode = "55555";

   List<Address> addresses = new List<Address>();
   addresses.Add(address);
   inst.Addresses = addresses;              
   db.Institutions.Add(inst);
   db.SaveChanges();

---

您可以通过在DbContext中重写OnModelCreating来控制一对多关系（以及外键定义）。类似于以下内容的操作应该可以工作：

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<Institution>().HasMany<Address>(i => i.Addresses)
        .WithRequired(i => i.Institution).HasForeignKey(i => i.Id);
}

模型创建时受保护的覆盖无效（DbModelBuilder modelBuilder）
{
modelBuilder.Entity（）有许多（i=>i.Addresses）
.WithRequired（i=>i.Institution）。HasForeignKey（i=>i.Id）；
}

用构造函数定义机构

public class Institution
{
    public Institution()
    {
            Addresses = new Addresses<Student>();
    }

    [Key]
    public int ID { get; set; }
    [Display(Name="Institution Name")]
    public string Name { get; set; }
    public virtual ICollection<Address> Addresses { get; set; }
}

---

如果主实体是自动递增的，则必须首先将其保存到db以生成其ID。然后将其分配给您的address对象。这就是为什么建议为您拥有的每个对象创建单独的存储库类的原因。这正是我所期望的。我只是不确定是否有某种内在的方式。

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<Institution>().HasMany<Address>(i => i.Addresses)
        .WithRequired(i => i.Institution).HasForeignKey(i => i.Id);
}

public class Institution
{
    public Institution()
    {
            Addresses = new Addresses<Student>();
    }

    [Key]
    public int ID { get; set; }
    [Display(Name="Institution Name")]
    public string Name { get; set; }
    public virtual ICollection<Address> Addresses { get; set; }
}

  Institution inst = new Institution();
   inst.Name = "Institution Name";
   Address address = new Address();
   address.Street1 = "1234 west main";      
   address.City = "Gotham";
   address.State = "WI";
   address.PostalCode = "55555";

   inst.Addresses.Add(addresses);              
   db.Institutions.Add(inst);
   db.SaveChanges();