php 去除bom 类

<?php
/**
* Created by JetBrains PhpStorm.
* User: 张华
* Date: 14-3-8
* Time: 下午12:21
* QQ: 746502560@qq.com
* To change this template use File | Settings | File Templates.
*/
$auto = 1;
function instance($dir){
$basedir=isset($dir)?$dir:'.';
checkdir($basedir);
}
function checkdir($basedir){
if ($dh = opendir($basedir)) {
while (($file = readdir($dh)) !== false) {
if ($file != '.' && $file != '..'){
if (!is_dir($basedir."/".$file)) {
echo "文件名：: $basedir/$file ".checkBOM("$basedir/$file")." <br>";
}else{
$dirname = $basedir."/".$file;
checkdir($dirname);
}
}
}
closedir($dh);
}
}
function checkBOM ($filename) {
global $auto;
$contents = file_get_contents($filename);
$contents = preg_replace( '/^(\xef\xbb\xbf)/', '', $contents );
$charset[1] = substr($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, $rest);
return ("<span style='color: #ff0000;'>找到bom错误,框架已自动删除.</span>");
} else {
return ("<span style='color: #ff0000;'>找到了一个bom 错误，请你更改.</span>");
}
}
else return ("没有找到bom错误.");
}
function rewrite ($filename, $data) {
$filenum = fopen($filename, "w");
flock($filenum, LOCK_EX);
fwrite($filenum, $data);
fclose($filenum);
}
?>