如何从ASP.NET核心身份类访问其他实体？

public class User
{
    public int Id { get; set; }
    public string UserName { get; set; }
    // 其他属性...

    public List<Product> Products { get; set; }
}

public class Product
{
    public int Id { get; set; }
    public string Name { get; set; }
    // 其他属性...

    public int UserId { get; set; }
    public User User { get; set; }
}

public class ApplicationDbContext : IdentityDbContext<User>
{
    public DbSet<Product> Products { get; set; }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);
        modelBuilder.Entity<Product>()
            .HasOne(p => p.User)
            .WithMany(u => u.Products)
            .HasForeignKey(p => p.UserId)
            .OnDelete(DeleteBehavior.Cascade);
    }
}

public class HomeController : Controller
{
    private readonly ApplicationDbContext _context;

    public HomeController(ApplicationDbContext context)
    {
        _context = context;
    }

    public async Task<IActionResult> Index()
    {
        var userId = User.FindFirst(ClaimTypes.NameIdentifier)?.Value;
        var user = await _context.Users
            .Include(u => u.Products)
            .FirstOrDefaultAsync(u => u.Id == int.Parse(userId));

        if (user == null)
        {
            return NotFound();
        }

        // 访问用户的产品信息
        var products = user.Products;

        return View(products);
    }
}

var user = await _context.Users
    .Include(u => u.Products)
    .FirstOrDefaultAsync(u => u.Id == int.Parse(userId));