我正在使用Entity Framework 6编写数据访问层。我想要的是，当我在DbContext上调用SaveChanges()方法时，它将保存实体以及通过导航属性关联的相关实体集。以下是我尝试执行的简单代码。

public class Customer
{
    public long ID { get; set; }
    public string Name { get; set; }
    public virtual IEnumerable<PhoneNumber> { get; set; }
}
public class PhoneNumber
{
    public long ID { get; set; }
    public string Number { get; set; }
}    
public class SampleContext : DbContext
{
    public virtual DbSet<Customer> Customers { get; set; }
    public virtual DbSet<PhoneNumber> PhoneNumbers { get; set; }
}
using(var context = new SampleContext())
{
     var customer = new Customer { ID = 1, Name = "John" };
     customer.PhoneNumbers = new PhoneNumbers[]
     {
          new PhoneNumber { ID = 1, Number = "1.111.1111111" },
          new PhoneNumber { ID = 2, Number = "1.111.1111112" }
     }
     context.Customers.Add(customer);
     context.SaveChanges();
}

字符串
上面的代码将客户保存在customers表中，但在PhoneNumbers表中不保存任何内容。