PHP 去掉 utf8格式文件中的bom头部

时间：2015-01-23 来源：西部数据作者：西部数据

我们有时要去掉utf8文档中头部我们经常会需要手工清除了,下面我整理了几个利用php程序清除 utf8格式文件中的bom头部方法.

PHP实例1,代码如下:

/**

* 去掉文件中的 bom头

* @var 0.1

* @author Chenwp

*/

function clearbom($contents){

    //UTF8 去掉文本中的 bom头

    $BOM = chr(239).chr(187).chr(191);

    return str_replace($BOM,'',$contents);

}

/**

* 去掉文件中的bom头

* @param object $fileName Description

* @return object    Description

*/

function clearfilebom($fileName){

    $c = file_get_contents($fileName);

    $c = clearbom($c);

    file_put_contents($fileName,$c);

}

PHP实例例2,代码如下:

<?php

//此文件用于快速测试UTF8编码的文件是不是加了BOM，并可自动移除

$basedir="."; //修改此行为需要检测的目录，点表示当前目录

$auto=1; //是否自动移除发现的BOM信息。1为是，0为否。

//以下不用改动

if ($dh = opendir($basedir)) {

       while (($file = readdir($dh)) !== false) {

       if ($file!='.' && $file!='..' && !is_dir($basedir."/".$file)) echo "filename: $file ".checkBOM("$basedir/$file")." <br>";

       }

       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);

}

//结束

?>

PHP实例3,代码如下:

<?php

// 设定你要清除BOM的根目录（会自动扫描所有子目录和文件）

$HOME = dirname(__FILE__);

// 如果是Windows系统，修改为：$WIN = 1;

$WIN = 0;

?>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">

<head>

<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

<title>UTF8 BOM 清除器</title>

<style>

body { font-size: 10px; font-family: Arial, Helvetica, sans-serif; background: #FFF; color: #000; }

.FOUND { color: #F30; font-size: 14px; font-weight: bold; }

</style>

</head>

<body>

<?php

$BOMBED = array();

RecursiveFolder($HOME);

echo '<h2>These files had UTF8 BOM, but i cleaned them:</h2><p class="FOUND">';

foreach ($BOMBED as $utf) { echo $utf ."<br />n"; }

echo '</p>';

// 递归扫描

function RecursiveFolder($sHOME) {

global $BOMBED, $WIN;

$win32 = ($WIN == 1) ? "\" : "/";

$folder = dir($sHOME);

$foundfolders = array();

while ($file = $folder->read()) {

  if($file != "." and $file != "..") {

   if(filetype($sHOME . $win32 . $file) == "dir"){

    $foundfolders[count($foundfolders)] = $sHOME . $win32 . $file;

   } else {

    $content = file_get_contents($sHOME . $win32 . $file);

    $BOM = SearchBOM($content);

    if ($BOM) {

     $BOMBED[count($BOMBED)] = $sHOME . $win32 . $file;

     // 移出BOM信息

     $content = substr($content,3);

     // 写回到原始文件

     file_put_contents($sHOME . $win32 . $file, $content);

    }

   }

  }

}

$folder->close();

if(count($foundfolders) > 0) {

  foreach ($foundfolders as $folder) {

   RecursiveFolder($folder, $win32);

  }

}

}

// 搜索当前文件是否有BOM

function SearchBOM($string) {

  if(substr($string,0,3) == pack("CCC",0xef,0xbb,0xbf)) return true;

  return false;

}

?>

</body>

</html>