实体框架代码首先生成数据库不正确
问题描述:
我认为实体框架在我的项目中生成数据库时有问题。奇怪的是,它只发生在一个案例中。这是“用户”和“播放列表”之间的一对多关系。一个用户有许多播放列表。实体框架代码首先生成数据库不正确
这里是我的代码,我使用了一些抽象类,在我的项目。 核心代码
Playlist类
public virtual User User { get; set; }
User类
public virtual ICollection<Playlist> Playlists { get; set; }
的完整代码:
泛型类:
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Web;
namespace xxx.Areas.admin.Models
{
public abstract class Generic
{
[Display(Name = "Ngày tạo")]
public DateTime? Created { get; set; }
[Display(Name = "Lần sửa cuối")]
public DateTime? Modified { get; set; }
[Display(Name = "Trạng thái")]
public bool? IsActive { get; set; }
}
}
Post类:
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Web;
namespace xxx.Areas.admin.Models
{
public abstract class Post : Generic
{
public string Title { get; set; }
public string Slug { get; set; }
public string Content { get; set; }
public string Image { get; set; }
public int Views { get; set; }
public bool? AllowComment { get; set; }
public User ModifiedBy { get; set; }
public virtual ICollection<Media> Medias { get; set; }
}
}
AlbumBase类:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using xxx.Areas.admin.Models.SongBase;
namespace xxx.Areas.admin.Models.AlbumBase
{
public abstract class AlbumBase : Post
{
public bool IsPublic { get; set; }
public bool IsFeatured { get; set; }
public int OldID { get; set; }
public string OldSlug { get; set; }
public virtual ICollection<Comment> Comments { get; set; }
}
}
Playlist类:
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Web;
using xxx.Areas.admin.Models.SongBase;
namespace xxx.Areas.admin.Models.AlbumBase
{
public class Playlist : AlbumBase
{
[Key]
public int PlaylistID { get; set; }
public virtual ICollection<Song> Songs { get; set; }
public virtual ICollection<Folk> Folks { get; set; }
public virtual ICollection<Instrumental> Instrumentals { get; set; }
public virtual User User { get; set; }
public Playlist()
{ }
public Playlist(string name)
{
Title = name;
Slug = Functions.URLFriendly(Title);
Views = 0;
OldID = 0;
AllowComment = true;
IsActive = true;
IsPublic = false;
IsFeatured = false;
Created = DateTime.Now;
}
}
}
和用户类:
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Web;
using baicadicungnamthang.Areas.admin.Models.AlbumBase;
using baicadicungnamthang.Areas.admin.Models.Social;
using baicadicungnamthang.DAL;
using ICB;
namespace xxx.Areas.admin.Models
{
public class User : Generic
{
[Key]
public int UserID { get; set; }
[Required(ErrorMessage = "Bạn phải nhập tên tài khoản"), StringLength(50)]
public string UserName { get; set; }
public string Password { get; set; }
public string HashPassword { get; set; }
[Required(ErrorMessage = "Bạn phải nhập địa chỉ email"), EmailAddress(ErrorMessage = "Địa chỉ email không hợp lệ")]
public string Email { get; set; }
[StringLength(50)]
public string NickName { get; set; }
public string FullName { get; set; }
public string Slug { get; set; }
public string Title { get; set; }
public string Phone { get; set; }
public string Avatar { get; set; }
public DateTime? DOB { get; set; }
[StringLength(1)]
public string Gender { get; set; }
public string Address { get; set; }
public int TotalLikes { get; set; }
public int TotalComments { get; set; }
public int Views { get; set; }
public string ActivationKey { get; set; }
public string RecoverKey { get; set; }
public DateTime? LastLogin { get; set; }
public int OldID { get; set; }
public virtual Role Role { get; set; }
public virtual ICollection<Comment> Comments { get; set; }
public virtual ICollection<Comment> RateComments { get; set; }
public virtual ICollection<Playlist> Playlists { get; set; }
public virtual ICollection<User> Friends { get; set; }
public virtual ICollection<Message> MessagesSent { get; set; }
public virtual ICollection<Message> MessagesReceived { get; set; }
public User()
{
Created = DateTime.Now;
IsActive = false;
TotalLikes = 0;
Views = 0;
OldID = 0;
}
public string getAvatar(int w, int h)
{
return Functions.getAvatarThumb(UserName, w, h);
}
public int getAge()
{
if (DOB == null)
{
return 0;
}
else
{
DateTime now = DateTime.Now;
int age = now.Year - DOB.Value.Year;
return age;
}
}
public string getGender()
{
if (Gender == "M")
{
return "Nam";
}
else if (Gender == "F")
{
return "Nữ";
}
else return "";
}
}
}
这首先是播放列表表生成从码:
正如你看到的,实体框架已经产生两列:User_UserID和User_UserID1从用户表的主键的用户ID。
我这样说是因为当我取消对该行 //公共虚拟用户用户{获得;组; } 并重建项目,这两列User_UserID和User_UserID1也消失了。
该问题只与用户和播放列表的关系发生了。与其他一对多方案(用户评论)相比,系统运作良好。
谁能给我一个建议?
答
问题是你有相同的实体之间的多个关系。
Playlist
对User
有2个引用(其中一个在Playlist
类中,一个在其基类Post
中)。
这混淆了实体框架,因为它不知道如何将关系映射,这就是为什么它在数据库中创建了太多的外键。
为了解决这个问题,你可以使用InverseProperty
属性来告诉它如何映射导航属性:
public class Playlist : AlbumBase
{
[Key]
public int PlaylistID { get; set; }
[InverseProperty("Playlists")]
public virtual User User { get; set; }
......
非常感谢您!我的问题解决了。 – 2013-05-01 16:33:21