config = $config; $this->times = $times; } /** * 执行打印请求 * @param $content * @return mixed */ abstract protected function printTicket($content); /** * 返回错误信息 * @return mixed */ public function getError() { return $this->error; } /** * 创建打印的内容 * @return string */ private function setContentText() { return ''; } }