参考文章：https://blog.csdn.net/LJFPHP/article/details/86135004

解决办法：

 $objWriter = \PHPExcel_IOFactory::createWriter($objPHPExcel, 'Excel2007'); 把上面的Excel2007换成Excel5就好了

 $objWriter = \PHPExcel_IOFactory::createWriter($objPHPExcel, 'Excel5');  

不过我的toexcel.php文件中早有excel5的代码，把excel7注释后，打开5的注释就可以了。

如下： //*生成xlsx文件 /* ob_end_clean();//清除缓冲区,避免乱码 header("Content-Type:text/html;charset=utf-8"); header('Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'); header('Content-Disposition: attachment;filename="'.$filename.'.xlsx"'); header('Cache-Control: max-age=0'); $objWriter=PHPExcel_IOFactory::createWriter($objPHPExcel,'Excel2007'); */

/* *生成xls文件 */ ob_end_clean();//清除缓冲区,避免乱码 header('Content-Type: application/vnd.ms-excel'); header('Content-Disposition: attachment;filename="'.$filename.'.xls"'); header('Cache-Control: max-age=0'); $objWriter = PHPExcel_IOFactory::createWriter($objPHPExcel, 'Excel5'); /**/