code: protected function retData(array $data)
      {
          $sign = $data['sign'];
          $data = ArrayUtil::removeKeys($data, ['sign']);
  
          $data = ArrayUtil::arraySort($data);
  
          // 支付宝新版本  需要转码
          foreach ($data as &$value) {
              $value = StrUtil::characet($value, $this->config->charset);
          }
  
          $data['sign'] = $sign;// sign  需要放在末尾
  
          return $data;
      }
docs: 处理支付宝的返回值并返回给客户端
  @param array $data
  @return string|array
  @author helei