创建实体模型多对多 CodeFirst Ef6

Posted 2023-02-16

【中文标题】创建实体模型多对多 CodeFirst Ef6

【英文标题】：Create entity model Many-To-Many CodeFirst Ef6

【发布时间】：2021-12-06 07:35:07

【问题描述】：

我希望 Db 使用 Code-First

我做了什么：

    public class Responses
    
        public int UserId  get; set; 
        public virtual AppUser AppUser  get; set; 

        public int QuestionId  get; set;  
        public virtual Question Question  get; set; 

        public string Answer  get; set; 

    
       
    public class Question
    
        public int idQuestion  get; set; 
        public string TextQuestion  get; set; 
        public ICollection<Responses> Responses   get; set; 
    

    public class AppUser : IdentityUser<int, AppUserLogin, AppUserRole, IdentityUserClaimBase>, ICRMRepository, IEditableEntity, IEntityBase
    
        public int idUser get;set;
        public ICollection<Responses> Responses  get; set; 

    

接下来我去 DbContext：

modelBuilder.Entity<Responses>()
                .HasKey(x => new x.UserId, x.QuestionId);

            modelBuilder.Entity<Responses>()
                .HasOne(x=>x.User)

无法解析符号“HasOne”

如果我想得到这样的 db，我该怎么办？

如何配置我与 fluent API 的关联？或者有没有更好的方法来创建关联表？

UPD

【参考方案1】：

更改响应类，将 AppUser 属性替换为 User

public class Responses
    
        public int UserId  get; set; 
        public virtual AppUser User get; set; 

       ........

    

并将此代码用于 Db 上下文

modelBuilder.Entity<Response>(entity =>

 entity.HasOne(d => User)
  .WithMany(p => p.Responses)
  .HasForeignKey(d => d.UserId);

 entity.HasOne(d => d.Question)
 .WithMany(p => p.Responses)
   .HasForeignKey(d => d.QuestionId;
);
 

【讨论】：

这很有效。我收到问题“类名用户无效”

@Boris 这只是一个错字。你可以修复它

我明白了。修复它并粘贴我的类型而不是“用户”我粘贴 AppUser

@Boris 现在工作了吗

我更新了我的问题，见图

【参考方案2】：

我可以解决它：

public class AppUser : IdentityUser<int, AppUserLogin, AppUserRole, IdentityUserClaimBase>, ICRMRepository, IEditableEntity, IEntityBase

    public ICollection<Response> Responses  get; set;  


public class Question

    public int Id  get; set; 
    public string TextQuestion  get; set; 
    public ICollection<Response> Responses   get; set; 


public class Response

    public int Id  get; set; 
    ***public int AppUserId  get; set; ***
    public int QuestionId  get; set; 
    
    public virtual AppUser AppUser  get; set; 
    public virtual Question Question  get; set; 

    public string Answer  get; set; 

数据库上下文：

public DbSet<Question> Questions  get; set; 
public DbSet<Response> Responses  get; set; 

EF6 明白我想要什么