一键去除网页BOM属性【解决网站乱码，程序头部空白，后台验证码不显示问题】

1.选用专业的编辑器，例如notepad++，sublime，editplus这样不会自动签名。

2.sublime通过如下操作File -> Save with Encoding -> UTF-8保存后即可去除bom

3.notepad++选中格式 -> 以UTF-8格式编码 选项即可去除

4.用如下方法可一次性清理网页所有文本文件的bom 

<?php  
$dir=dirname(__FILE__);if(isset($_GET["act"]) && $_GET["act"] == "del" ){   //Del the file!!
$filename=basename($_SERVER['PHP_SELF']);
@unlink($filename);
exit('Error:File Not Found!');
}echo "The document:".$dir."&nbsp;&nbsp;<a href=\"?act=del\" >[Del the delbom.php file]</a><BR/>";if (!is_dir($dir))
die("$dir not exists");
$auto = 1;  
checkdir($dir);  
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/>\n";  }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, $rest);  return ("<font color=red> BOM found, automatically removed.</font>\n");  } else {  return ("<font color=red>BOM found.</font>\n");  }  
}  
else return ("BOM Not Found.\n");  
}  
function rewrite ($filename, $data) {  
$filenum = fopen($filename, "w");  
flock($filenum, LOCK_EX);  
fwrite($filenum, $data);  
fclose($filenum);  
}  
?>