PHP 传参过滤

<?php

class class_replace{

function htmldecode($str){

if(empty($str)) return;if($str=="") return $str;

$str=str_replace("&","",$str);

$str=str_replace(">","",$str);

$str=str_replace("<","",$str);

$str=str_replace("chr(32)","",$str);

$str=str_replace("chr(9)","",$str);

$str=str_replace(chr(34),"",$str);

$str=str_replace("\"","",$str);

$str=str_replace(chr(39),"",$str);

$str=str_replace("","",$str);

$str=str_replace("'","",$str);

$str=str_replace("select","",$str);

$str=str_replace("join","",$str);

$str=str_replace("union","",$str);

$str=str_replace("where","",$str);

$str=str_replace("insert","",$str);

$str=str_replace("delete","",$str);

$str=str_replace("update","",$str);

$str=str_replace("like","",$str);

$str=str_replace("drop","",$str);

$str=str_replace("create","",$str);

$str=str_replace("modify","",$str);

$str=str_replace("rename","",$str);

$str=str_replace("alter","",$str);

$str=str_replace("cas","",$str);

$str=str_replace("replace","",$str);

$str=str_replace("%","",$str);

$str=str_replace("or","",$str);

$str=str_replace("and","",$str);

$str=str_replace("!","",$str);

$str=str_replace("xor","",$str);

$str=str_replace("not","",$str);

$str=str_replace("user","",$str);

$str=str_replace("||","",$str);

$str=str_replace("<","",$str);

$str=str_replace(">","",$str);

return $str;

}

}

//使用方法：$guolv=new class_replace();

//实例化

//$username=$guolv->htmldecode($_POST["username"]);

//使用例子?>