使用导航属性的 MVC 代码优先

Question

这是一个简单的 cmets 和消息系统。他们还有两个演员：FromActor 和 ToActor... 我的代码是这样的：

 public class Comment
 {        
    public int Id { get; set; } 
    public string Title { get; set; }
    public string Text { get; set; }
    public virtual Actor AboutActor { get; set; }        
    public virtual Actor FromActor { get; set; }
 }

 public class Message
 {
    public int Id { get; set; }       
    public string Title { get; set; }       
    public string Text { get; set; }       
    public virtual Actor ToActor { get; set; }
    public virtual Actor FromActor { get; set; } 
}

public class Actor  
{       
    public int Id { get; set; }       
    public string Username { get; set; }
    public virtual List<Comment> Comments { get; set; }
    public virtual List<Message> Messages { get; set; }
}

我首先在代码中遇到了导航道具的问题。这是真的吗？我应该如何编辑导航链接或模型以获得解决方案？谢谢...

Answer 1

您应该在Actor 类中添加对Comments 和Messages 的附加引用，并使用InversePropertyAttribute 将它们映射到相应的属性。也可以直接声明FKs：

public class Comment
{        
    //other stuff...
    public int AboutActorId { get; set; }        
    public int FromActorId { get; set; }
    public virtual Actor AboutActor { get; set; }        
    public virtual Actor FromActor { get; set; }
}

public class Message
{
    //other stuff...
    public int ToActorId { get; set; }        
    public int FromActorId { get; set; }
    public virtual Actor ToActor { get; set; }
    public virtual Actor FromActor { get; set; } 
}

public class Actor  
{       
    public int Id { get; set; }       
    public string Username { get; set; }

    [InverseProperty("AboutActor")]
    public virtual ICollection<Comment> CommentsAbout { get; set; }
    [InverseProperty("FromActor")]
    public virtual ICollection<Comment> CommentsFrom { get; set; }

    [InverseProperty("ToActor")]
    public virtual ICollection<Message> MessagesTo { get; set; }
    [InverseProperty("FromActor")]
    public virtual ICollection<Message> MessagesFrom { get; set; }
}