bind_param问题是：// include PHPExcel library here
$objReader = new PHPExcel_Reader_Excel5();
$objReader->setReadDataOnly(true);
$objPHPExcel = $objReader->load( "file.xls" );
// get excel file rows as array
$rowIterator = $objPHPExcel->getActiveSheet()->getRowIterator();
数组始终具有与excel文件中相同的元素（行）序列吗？可以保证吗？