我可以在Entity Framework 5，c＃中的兩個實體之間創建多個關聯嗎？

Question

例如我有2個實體：

public class Department 
{ 
    public Guid Id { get; set; } 
    public string Name { get; set; } 
    public ICollection<Employee> Employees { get; set; } 
    public Employee Manager { get; set; } 
} 

public class Employee 
{ 
    public Guid Id { get; set; } 
    public string FullName { get; set; } 

    [ForeignKey("DepartmentId")] 
    public Department Department { get; set; } 
    public Guid DepartmentId { get; set; } 
    public string Position { get; set; } 
} 

我知道我可以聯繫起來（因爲我已經做了:) Department.Employees與Employee.Id（和逆：Employee.Department與Department.Id）。

問題：
1）這是一個還是兩個關聯？

2）我可以創建Department.Manager和Employee.Id之間的第二關聯？ Don'想要將經理存儲在另一個表中，因此他們也存儲在Employee表中並且在Position字段「經理」中有。

Answer 1

定義關係如下。

protected override void OnModelCreating(DbModelBuilder modelBuilder) 
{ 
    modelBuilder.Entity<Department>() 
     .HasRequired(a => a.Manager) 
     .WithMany() 
     .HasForeignKey(a => a.EmployeeId); 
} 

如果您想延遲加載和更改跟蹤，您也希望它們也是虛擬的。

public class Department 
{ 
    public Guid Id { get; set; } 
    public string Name { get; set; } 
    public virtual ICollection<Employee> Employees { get; set; } 
    public virtual Employee Manager { get; set; } 
}