您好我正在尝试为用户和角色之间的多对多关系设置我的实体框架。
下图显示了数据库中的内容:
用户模型是:
public class User : IEntity
{
public virtual int UserId { get; set; }
[Column(TypeName = "varchar")]
[StringLength(100)]
public virtual string UserName { get; set; }
[Column(TypeName = "varchar")]
[StringLength(100)]
public virtual string FirstName { get; set; }
[Column(TypeName = "varchar")]
[StringLength(100)]
public virtual string LastName { get; set; }
[Column(TypeName = "varchar")]
[StringLength(200)]
public virtual string EmailAddress { get; set; }
public int AreaId { get; set; }
[Column(TypeName = "varchar")]
[StringLength(64)]
public string CreatedByUserName { get; set; }
public DateTime CreatedDateTime { get; set; }
[Column(TypeName = "varchar")]
[StringLength(64)]
public string LastModifiedByUserName { get; set; }
public DateTime? LastModifiedDateTime { get; set; }
//Navigation properties
//public virtual Role Role { get; set; }
public virtual Area Area { get; set; }
public virtual ICollection<Role> Roles { get; set; }
}
角色模型是:
public class Role : IEntity
{
public int RoleId { get; set; }
[Column(TypeName = "varchar")]
[StringLength(100)]
public string Name { get; set; }
[Column(TypeName = "varchar")]
[StringLength(1000)]
public string Description { get; set; }
[Column(TypeName = "varchar")]
[StringLength(64)]
public string CreatedByUserName { get; set; }
public DateTime CreatedDateTime { get; set; }
[Column(TypeName = "varchar")]
[StringLength(64)]
public string LastModifiedByUserName { get; set; }
public DateTime? LastModifiedDateTime { get; set; }
//Navigation Properties
public ICollection<User> Users { get; set; }
}
UserRole是:
public class UserRole
{
public int UserId { get; set; }
public int RoleId { get; set; }
//Navigation properties
public virtual User User { get; set; }
public virtual Role Role { get; set; }
}
所以我认为我的设置很好但是在我的代码中我会像:
var roles = from r in user.Roles
select r.Name;
它射出了自己的错误:
Server Error in '/' Application.
Invalid object name 'dbo.RoleUser'.
所以我在上下文中添加了以下内容:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<User>()
.HasMany(i => i.Roles)
.WithMany(u => u.Users);
}
但是现在我遇到了错误:
>'/'应用程序中的服务器错误。 列名称“Role_RoleId”无效。 列名称“User_UserId”无效。所以我肯定没有正确设置这里的东西。安妮可以指出我正确的方向吗?
答案 0 :(得分:9)
您不需要将链接表UserRole
建模为类,因为它只有表的主键参与关系。因此,请删除UserRole
类。
如果要对现有数据库建模,EF可能会将链接表名称推断为RoleUser
。为避免这种情况,您可以按如下方式配置链接表。
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<User>()
.HasMany(i => i.Roles)
.WithMany(u => u.Users)
.Map(m =>
{
m.ToTable("UserRole");
m.MapLeftKey("UserId");
m.MapRightKey("RoleId");
});
}