PHP 下载文件时自动添加bom头的步骤

// 文件名  $filename = "www.111cn.net .csv";    header('Expires: ' . gmdate('D, d M Y H:i:s', $_SERVER['REQUEST_TIME'] + 10) . ' GMT');  header('Cache-Control: max-age=10');  //header('Content-Type: application/vnd.ms-excel; charset=utf-8');  header('Content-Type: text/csv; charset=utf-8');  header("Content-Disposition: attachment; filename={$filename}");    // 如果结果中有提示信息，则把第一行输出改为提示信息文字  $out = "xEFxBBxBF";// 加上bom头，系统自动默认为UTF-8编码  if (!empty($extra['notice'])) {   $out .= "{$extra['notice']}rn";  }   // 输出  foreach ($table as $row) {   $out .= implode(",", $row) . "rn";  }    /* if (mb_detect_encoding()($out) == 'UTF-8') {   $out = iconv("UTF-8//IGNORE", "GBK", $out);  } */  echo $out;