php 過濾特殊字元及sql防注入代碼

php 過濾特殊字元及sql防注入代碼
<?php
//方法一
//過濾',",sql語名
addslashes();

//方法二，去除所有html標籤

strip_tags();

//方法三過濾可能產生代碼

function php_sava($str)
{
    $farr = array(
        "/s+/",                                                                                         
        "/<(/?)(script|i?frame|style|html|body|title|link|meta|?|%)([^>]*?)>/isU",  
        "/(<[^>]*)on[a-zA-Z]+s*=([^>]*>)/isU",                                     
     
   );
   $tarr = array(
        " ",
        "＜\1\2\3＞",           //如果要直接清除不安全的標籤，這裡可以留空
        "\1\2",
   );

  $str = preg_replace( $farr,$tarr,$str);
   return $str;
}

//php sql防注入代碼

class sqlin
{

//dowith_sql($value)
function dowith_sql($str)
{
   $str = str_replace("and","",$str);
   $str = str_replace("execute","",$str);
   $str = str_replace("update","",$str);
   $str = str_replace("count","",$str);
   $str = str_replace("chr","",$str);
   $str = str_replace("mid","",$str);
   $str = str_replace("master","",$str);
   $str = str_replace("truncate","",$str);
   $str = str_replace("char","",$str);
   $str = str_replace("declare","",$str);
   $str = str_replace("select","",$str);
   $str = str_replace("create","",$str);
   $str = str_replace("delete","",$str);
   $str = str_replace("insert","",$str);
   $str = str_replace("'","",$str);
   $str = str_replace(""","",$str);
   $str = str_replace(" ","",$str);
   $str = str_replace("or","",$str);
   $str = str_replace("=","",$str);
   $str = str_replace("%20","",$str);
   //echo $str;
   return $str;
}
//aticle()防SQL注入函數//php教程
function sqlin()
{
   foreach ($_GET as $key=>$value)
   {
       $_GET[$key]=$this->dowith_sql($value);
   }
   foreach ($_POST as $key=>$value)
   {
       $_POST[$key]=$this->dowith_sql($value);
   }
}
}

$dbsql=new sqlin();
?>
===================================================================================
使用方式：
將以上代碼複製建立一個sqlin.php的檔案，然後包含在有GET或者POST資料接收的頁面
原理：
將所有的SQL關鍵字替換為空白
本代碼在留言本中不能使用，若要在留言本中使用請替換其中的
.......
$str = str_replace("and","",$str);
到
$str = str_replace("%20","",$str);
...
的代碼為:
$str = str_replace("and","&#97;nd",$str);
$str = str_replace("execute","&#101;xecute",$str);
$str = str_replace("update","&#117;pdate",$str);
$str = str_replace("count","&#99;ount",$str);
$str = str_replace("chr","&#99;hr",$str);
$str = str_replace("mid","&#109;id",$str);
$str = str_replace("master","&#109;aster",$str);
$str = str_replace("truncate","&#116;runcate",$str);
$str = str_replace("char","&#99;har",$str);
$str = str_replace("declare","&#100;eclare",$str);
$str = str_replace("select","&#115;elect",$str);
$str = str_replace("create","&#99;reate",$str);
$str = str_replace("delete","&#100;elete",$str);
$str = str_replace("insert","&#105;nsert",$str);
$str = str_replace("'","&#39;",$str);
$str = str_replace(""","&#34;",$str);

 

?>