Codeigniter CORS 策略：没有“Access-Control-Allow-Origin”错误如何解决？

    public function __construct()
                parent::__construct();
                $this->load->model('api_model');
                $this->load->library('form_validation');
                Header('Access-Control-Allow-Origin: *'); //for allow any domain, insecure
                Header('Access-Control-Allow-Headers: *'); //for allow any headers, insecure
                Header('Access-Control-Allow-Methods: GET, POST, OPTIONS, PUT, DELETE'); //method allowed
        header('Access-Control-Allow-Origin: website_url');
        header("Content-Type: application/json; charset=UTF-8");
        Header('Access-Control-Allow-Methods: GET, POST, OPTIONS, PUT, DELETE'); //method allowed