Asp.Net Core 6中扩展Identity User无法获取数据问题求助

我在.NET Core 6中采用工作单元（Unit of Work）、仓储模式及内置依赖注入搭建网站，其他实体可通过工作单元正常获取数据库数据，但通过继承IdentityUser实现ApplicationUser扩展Asp.Net Users表字段后，调用以下代码返回的users和users2均为null：

var users = _userRepository.GetAll().ToList();
var users2 = _unitOfWork.ApplicationUsers.GetAll();

相关代码实现 #

HomeController代码 #

public class HomeController : Controller
{
    private readonly ILogger<HomeController> _logger;
    private readonly IUnitOfWork _unitOfWork;
    private IApplicationUserRepository _userRepository;

    public HomeController(ILogger<HomeController> logger, IUnitOfWork unitOfWork, IApplicationUserRepository userRepository)
    {
        _logger = logger;
        _unitOfWork = unitOfWork;
        _userRepository = userRepository;
    }

    public IActionResult Index()
    {
        var users = _userRepository.GetAll().ToList();
        return View(users);
    }
}

ApplicationDbContext及ApplicationUser代码 #

public class ApplicationDbContext : IdentityDbContext
{
    public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
       : base(options)
    {}
    public DbSet<ApplicationUser> ApplicationUsers { get; set; }
}

public class ApplicationUser : IdentityUser
{
    [Required]
    public string Name { get; set; }
    public string? StreetAddress { get; set; }
}

仓储及工作单元代码 #

public class ApplicationUserRepository : Repository<ApplicationUser>, IApplicationUserRepository
{
    private readonly ApplicationDbContext _db;
    public ApplicationUserRepository(ApplicationDbContext db):base(db)
    {
        _db = db;
    }
}
public interface IApplicationUserRepository : IRepository<ApplicationUser>
{
}

public interface IUnitOfWork
{
    IApplicationUserRepository ApplicationUsers { get; }
}

public class UnitOfWork : IUnitOfWork
{
    private ApplicationDbContext _db;
    public IApplicationUserRepository ApplicationUsers { get; private set; } 

    public UnitOfWork(ApplicationDbContext db)
    {
        _db = db;
        ApplicationUsers = new ApplicationUserRepository(_db);
    }
}

服务注册代码 #

builder.Services.AddIdentity<IdentityUser, IdentityRole>(options => options.SignIn.RequireConfirmedAccount = true)
    .AddDefaultTokenProviders()
    .AddEntityFrameworkStores<ApplicationDbContext>();

builder.Services.AddScoped<IUnitOfWork, UnitOfWork>();
builder.Services.AddScoped<IApplicationUserRepository, ApplicationUserRepository>();

builder.Services.AddDbContextPool<ApplicationDbContext>(options => options.UseSqlServer(connectionString));

解决方案 #

问题核心是Identity框架与自定义用户实体的映射不匹配，按以下步骤修复：

1. 修正ApplicationDbContext的继承泛型
   将IdentityDbContext改为IdentityDbContext<ApplicationUser>，让EF Core明确使用自定义用户实体映射到Users表：

   public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
   {
       public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
          : base(options)
       {}
       // 可保留DbSet<ApplicationUser>，但IdentityDbContext已内置对用户实体的DbSet，并非必须
       public DbSet<ApplicationUser> ApplicationUsers { get; set; }
   }
   

2. 修正Identity服务注册的泛型参数
   将AddIdentity<IdentityUser, IdentityRole>改为AddIdentity<ApplicationUser, IdentityRole>，确保Identity框架使用你的自定义用户实体：

   builder.Services.AddIdentity<ApplicationUser, IdentityRole>(options => options.SignIn.RequireConfirmedAccount = true)
       .AddDefaultTokenProviders()
       .AddEntityFrameworkStores<ApplicationDbContext>();
   

3. 验证仓储基类Repository的GetAll实现
   确认Repository<T>基类的GetAll()方法正确返回实体集合，示例实现：

   public class Repository<T> : IRepository<T> where T : class
   {
       protected readonly ApplicationDbContext _db;
       public Repository(ApplicationDbContext db)
       {
           _db = db;
       }
   
       public IEnumerable<T> GetAll()
       {
           return _db.Set<T>().ToList();
       }
   }
   

4. 更新数据库迁移（若已生成过迁移）
   重新生成迁移并更新数据库，确保Users表包含新增的Name和StreetAddress字段：

   Add-Migration UpdateApplicationUser
   Update-Database
   

完成以上操作后，通过仓储或工作单元即可正常获取ApplicationUser的数据。

内容的提问来源于stack exchange，提问作者Reest