bom.php是什么？能详细介绍一下吗？

本文共计172个文字，预计阅读时间需要1分钟。

phpfunction checkBOM($filename) { global $auto; $contents=file_get_contents($filename); $charset[1]=substr($contents, 0, 1); $charset[2]=substr($contents, 1);}

bom.php

"; }else{ $dirname = $basedir."/".$file; checkdir($dirname); } } } closedir($dh); } } function checkBOM ($filename) { global $auto; $contents = file_get_contents($filename); $charset[1] = substr($contents, 0, 1); $charset[2] = substr($contents, 1, 1); $charset[3] = substr($contents, 2, 1); if (ord($charset[1]) == 239 && ord($charset[2]) == 187 && ord($charset[3]) == 191) { if ($auto == 1) { $rest = substr($contents, 3); rewrite ($filename, $rest); return ("BOM found, automatically removed."); } else { return ("BOM found."); } } else return ("BOM Not Found."); } function rewrite ($filename, $data) { $filenum = fopen($filename, "w"); flock($filenum, LOCK_EX); fwrite($filenum, $data); fclose($filenum); } ?>