PHP防注入和XSS攻击通用过滤规则
放在index.php头部.

<?php
//php防注入和XSS攻击通用过滤. 
$_GET     && SafeFilter($_GET);
$_POST    && SafeFilter($_POST);
$_COOKIE  && SafeFilter($_COOKIE);
function SafeFilter (&$arr){
  $ra=Array('/([\x00-\x08,\x0b-\x0c,\x0e-\x19])/','/script/','/javascript/','/vbscript/','/expression/','/applet/','/meta/','/xml/','/blink/','/link/','/style/','/embed/','/object/','/frame/','/layer/','/title/','/bgsound/','/base/','/onload/','/onunload/','/onchange/','/onsubmit/','/onreset/','/onselect/','/onblur/','/onfocus/','/onabort/','/onkeydown/','/onkeypress/','/onkeyup/','/onclick/','/ondblclick/','/onmousedown/','/onmousemove/','/onmouseout/','/onmouseover/','/onmouseup/','/onunload/');
  if (is_array($arr)){
    foreach ($arr as $key => $value){
      if(!is_array($value)){
        if (!get_magic_quotes_gpc()){             //不对magic_quotes_gpc转义过的字符使用addslashes(),避免双重转义。
          $value=addslashes($value);           //给单引号（'）、双引号（"）、反斜线（\）与 NUL（NULL 字符）加上反斜线转义
        }
        $value=preg_replace($ra,'',$value);     //删除非打印字符，粗暴式过滤xss可疑字符串
        $arr[$key]     = htmlentities(strip_tags($value)); //去除 HTML 和 PHP 标记并转换为 HTML 实体
      }else{
        SafeFilter($arr[$key]);
      }
    }
  }
}