EF 5.0 Code First双向导航小孩的外键ID [英] EF 5.0 Code First Two way navigation withought foreign key id in child

问题描述

我有以下课程

  public class Employer 
 {
 [Key] 
 public Int64 EmployerID {get;组; } 
 public String CompanyName {get;组; } 
 public virtual List< Employee>员工{get;组; 
} 
 
 public class Employee 
 {
 [Key] 
 public Int64 EmployeeID {get;组; } 
 public String EmployeeName {get;组; } 
 public virtual Employer EmployerInfo {get;组; } 
} 
  

在数据库上下文中，我将关系设置为

$ （）
.HasMany（p => p.Employees）
.WithRequired（）
.Map（x => x.MapKey（EmployerID））;

执行一些操作后，使用Employee表创建数据库，具有 EmployerID 作为外键和一个额外的键 EmployerInfo_EmployerID 。

现在，当我提取雇主数据时，我我得到员工的细节。
但是当我尝试获取员工数据时，我将EmployerInfo作为空值。这是因为我需要从员工到雇主信息的关系。

如何在此上下文中设置双向关系？

解决方案

你需要更新你的流利，所以你的关系映射包含两端：

  modelBuilder.Entity< Employer>（）
 .HasMany（p => p.Employees）
 .WithRequired（e => e.EmployerInfo）
 .Map（x => ; x.MapKey（EmployerID））; 
  

I have following classes

public class Employer
{
    [Key]
    public Int64 EmployerID { get; set; }
    public String CompanyName { get; set; }
    public virtual List<Employee> Employees { get; set; }
}

public class Employee
{
    [Key]
    public Int64 EmployeeID { get; set; }
    public String EmployeeName { get; set; }
    public virtual Employer EmployerInfo { get; set; }
}

In the Database context I have set the relation as

modelBuilder.Entity<Employer>()
.HasMany(p => p.Employees)
.WithRequired()
.Map(x => x.MapKey("EmployerID"));

After executing some actions, database gets created with Employee table having EmployerID as foreign key and one extra key EmployerInfo_EmployerID.

Now when I fetch employer data, I am getting employee details with it. But when I tried to fetch employee data I am getting EmployerInfo as null. This is because I need relationship from Employee to EmployerInfo.

How do I set the bi-directional relationship in this context?

解决方案

You need to update your fluent so your relationship mapping contains both ends:

        modelBuilder.Entity<Employer>()
        .HasMany(p => p.Employees)
        .WithRequired(e => e.EmployerInfo)
        .Map(x => x.MapKey("EmployerID"));

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