php 过滤特殊字符及sql防注入代码

<?php 
//方法一 
//过滤&#39;,",sql语名 
addslashes(); 
 
//方法二，去除所有html标签 
 
strip_tags(); 
 
//方法三过滤可能产生代码 
 
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(  
" ",  
"<123>",           //如果要直接清除不安全的标签，这里可以留空  
"12",  
   ); 
  $str = preg_replace( $farr,$tarr,$str);  
   return $str;  
} 
 
//php sql防注入代码 
 
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); 
   $str = str_replace("&#39;","",$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 $str; 
} 
//aticle()防SQL注入函数//php教程 
function sqlin() 
{ 
   foreach ($_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:将以上代码复制新建一个sqlin.php的文件,然后包含在有GET或者POST数据接收的页面.

原理:将所有的SQL关键字替换为空,本代码在留言本中不能使用,若要在留言本中使用请替换其中的.

$str = str_replace("and","",$str); 
//到: 
$str = str_replace("%20","",$str);//的代码为: 
$str = str_replace("and","and",$str); 
$str = str_replace("execute","execute",$str); 
$str = str_replace("update","update",$str); 
$str = str_replace("count","count",$str); 
$str = str_replace("chr","chr",$str); 
$str = str_replace("mid","mid",$str); 
$str = str_replace("master","master",$str); 
$str = str_replace("truncate","truncate",$str); 
$str = str_replace("char","char",$str); 
$str = str_replace("declare","declare",$str); 
$str = str_replace("select","select",$str); 
$str = str_replace("create","create",$str); 
$str = str_replace("delete","delete",$str); 
$str = str_replace("insert","insert",$str); 
$str = str_replace("'","'",$str); 
$str = str_replace("\"",""",$str);

永久地址：

转载随意~请带上教程地址吧^^