从MVC Controller类中删除数据库调用的最佳实践

public class UserRepository
{
    public User GetUser(int id)
    {
        // 数据库操作，例如查询用户
    }
}

public class UserService
{
    private readonly UserRepository _userRepository;

    public UserService(UserRepository userRepository)
    {
        _userRepository = userRepository;
    }

    public User GetUser(int id)
    {
        return _userRepository.GetUser(id);
    }
}

public class UserController : Controller
{
    private readonly UserService _userService;

    public UserController(UserService userService)
    {
        _userService = userService;
    }

    public ActionResult GetUser(int id)
    {
        var user = _userService.GetUser(id);
        return View(user);
    }
}