php去除bom

碰到bom是很头疼的事情，用了很多方法，比如notepad++保存无bom之类的都不管用。

后来执行了下面一段代码，总算把整个项目全部去除了

这个是循环目录所有文件去删除bom，不管是页面头部还是中间

<?php
if (isset($_GET['dir'])){ //config the basedir
    $basedir=$_GET['dir'];
}else{
    $basedir = '.';
}

$auto = 1;

checkdir($basedir);

function checkdir($basedir){
    if ($dh = opendir($basedir)) {
        while (($file = readdir($dh)) !== false) {
            if ($file != '.' && $file != '..'){
                if (!is_dir($basedir."/".$file)) {
                    echo "filename
$basedir/$file ".checkBOM("$basedir/$file")." <br>";
                }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 ("<font color=red>BOM found, automatically removed.</font>");
        } else {
            return ("<font color=red>BOM found.</font>");
        }
    }
    else return ("BOM Not Found.");
}

function rewrite ($filename, $data) {
    $filenum = fopen($filename, "w");
    flock($filenum, LOCK_EX);
    fwrite($filenum, $data);
    fclose($filenum);
}
?>