Question

我有一个继承自activeentity的课程部门

public class ActiveEntity : Entity, IActive
    {
        public ActiveEntity()
        {
            IsActive = true;
        }
        [Key]
        [DatabaseGenerated(DatabaseGeneratedOption.None)]
        public Guid Id { get; set; }
        public bool IsActive { get; set; }
        [Timestamp, ScaffoldColumn(false), DatabaseGenerated(System.ComponentModel.DataAnnotations.DatabaseGeneratedOption.Computed)]
        public Byte[] Timestamp { get; set; }
        [ScaffoldColumn(false)]
        public string CreationUserId { get; set; }
        [ScaffoldColumn(false)]
        public string LastModifiedUserId { get; set; }
    }
    public class Department:ActiveEntity    
    {
        public Department()
        {
            this.Address = new DepartmentAddress();
        }
        [StringLength(9),MinLength(9),MaxLength(9)]
        public string Name { get; set; }

        public Guid ManagerId { get; set; }
        [UIHint("AjaxDropdown")]
        public User Manager { get; set; }
        public Guid? AddressId { get; set; }
        public DepartmentAddress Address { get; set; }

        public ICollection<OverheadRate> OverheadRates { get; set; }


    }

我只是使用注释没有Fluent API。数据保存到数据Sql Server 2008就好了但是地址对象永远不会被实例化，即使我有上下文使用include

return c.Set<Department>().Include(d => d.Address).Include(d => d.Manager).Where(predicate);

返回数据我运行sql profiler然后运行查询它返回正确的数据。

有任何想法或建议吗？

Answer 1

删除在this.Address = new DepartmentAddress();构造函数中实例化地址（Department）。在默认构造函数中实例化导航引用是邪恶的，并且具有令人讨厌的副作用，如：

What would cause the Entity Framework to save an unloaded (but lazy loadable) reference over existing data?

EF 4.1 Code First: Why is EF not setting this navigation property?

Code First Object未正确实例化

1 个答案: