public function importexcel()
  {
    try {
      //获取表格的大小，限制上传表格的大小
      if ($_files['file']['size'] > 10 * 1024 * 1024) { //文件过大
        log_debug($log_title . 'end === msg：' . '文件过大');
        parent::endback(['state' => 0, 'msg' => '文件过大']);
      }
 
      //限制上传表格类型
      $ext = substr(strrchr($_files['file']["name"], '.'), 1);
      if ($ext != 'xls' && $ext != 'xlsx') {
        log_debug($log_title . 'end === msg：' . '文件格式不正确');
        parent::endback(['state' => 0, 'msg' => '上传文件必须为excel表格']);
      }
 
 
      //读取表格
      $filename = $_files['file']['tmp_name'];
      $reader = iofactory::createreader('xlsx'); //xls,xlsx都可读取
      $canread = $reader->canread($filename);
      if (!$canread) {
        log_debug($log_title . 'end，文件格式不正确，sql：' . db::name('')->getlastsql());
        parent::endback(['state' => 0, 'msg' => '文件格式不正确', 're_login' => false]);
      }
 
      $spreadsheet = $reader->load($filename); //载入excel表格
      $worksheet = $spreadsheet->getactivesheet(); //选中sheet表
      $highestrow = $worksheet->gethighestrow(); // 总行数
//      $highestcolumn = $worksheet->gethighestcolumn(); // 总列数
 
      if (!(0 < $highestrow)) {
        log_debug($log_title . 'end，文件内容空，sql：' . db::name('')->getlastsql());
        parent::endback(['state' => 0, 'msg' => '文件没有数据', 're_login' => false]);
      }
 
 
      //循环读取--有效判断
      $sst_word_arr = []; //存放敏感词的数组
      for ($row = 1; $row <= $highestrow; $row++) {
        //取列数a列的数据
        $tmp_word = $spreadsheet->getactivesheet()->getcell('a' . $row)->getvalue();
        if ('' != trim($tmp_word) && null != $tmp_word) {
          $sst_word_arr[] = $tmp_word;
          break; //发现有效数据,直接退出,接下来插入数据
        }
      }
//      $sst_word_arr = array_unique($sst_word_arr);
 
      if (empty($sst_word_arr)) {
        log_debug($log_title . 'end，文件无有效数据，sql：' . db::name('')->getlastsql());
        parent::endback(['state' => 0, 'msg' => '文件无有效数据', 're_login' => false]);
      }
 
      //判断和数据库操作
      for ($row = 2; $row <= $highestrow; $row++) {
        //取列数a列的数据
        $tmp_old_car_num = $spreadsheet->getactivesheet()->getcell('a' . $row)->getvalue();
 
        $car_num = trim($tmp_old_car_num);
        if ('' != $car_num && null != $car_num) {
          //数据库操作
          }
        }
      }
 
      $ret_arr = [
        'state' => 1,
         //返回数据
      ];
 
      log_debug($log_title . 'end，success');
      parent::endback($ret_arr);
  } catch (\exception $e) {
      //
    }
  }

namespase app\test;
use phpoffice\phpspreadsheet\iofactory;
use phpoffice\phpspreadsheet\spreadsheet;
use phpoffice\phpspreadsheet\writer\xlsx;
class test {
  public function carnumsexport()
  {
    $log_title = '测试 => 车牌列表导出[' . __method__ . '] ';
    try {
 
      $file_name = '《车牌列表》from y8zh - ' . $user_info['uid'] . '.xlsx';
      $file_relative_path = parent::$module_name . directory_separator . 'fcb_car_nums' . directory_separator;
      $file_path = parent::$api_file_root_path . $file_relative_path;
 
      // 已生成过则直接返回
      if (file_exists($file_path . $file_name)) {
        $ret_arr = [
          'state' => 1,
          'download_url' => parent::$api_file_get_url . $file_relative_path . $file_name,
        ];
        parent::endback($ret_arr);
      }
 
      if (!is_dir($file_path)) {
        mkdir($file_path, 0777, true);
      }
 
      $spreadsheet = new spreadsheet();
      $sheet = $spreadsheet->getactivesheet();
 
      //获取所有车牌号
      $car_nums = db::connect('db_config_yun')->name('vechicle')->column('distinct number');
 
      $i = 1;
        $sheet->setcellvalue('a' . $i, '车牌号')->getstyle('a' . $i)->getfont()->setbold(true);
        $i++;
 
      // 表内容
      if (!empty($car_nums)) {
        foreach ($car_nums as $k_c => $v_c) {
          $sheet->setcellvalue('a' . $i, $v_c);
          $i++;
        }
 
      }
 
      $writer = new xlsx($spreadsheet);
      $writer->save($file_path . $file_name);
      $ret_arr = [
        'state' => 1,
        'download_url' => parent::$api_file_get_url . $file_relative_path . $file_name,
      ];
 
      log_debug($log_title . 'end === download_url：' . $ret_arr['download_url']);
      parent::endback($ret_arr);
  } catch (\exception $e) {
      //
    }
  }
}