php SQL防注入代码集合

<?php 
/** 
* 防sql注入 
* @author: zhuyubing@gmail.com 
* */ 
/** 
* reject sql inject 
*/ 
if (!function_exists (quote)) 
{ 
function quote($var) 
{ 
if (strlen($var)) 
{ 
$var=!get_magic_quotes_gpc() ? $var : stripslashes($var); 
$var = str_replace("'","\'",$var); 
} 
return "'$var'"; 
} 
} 
if (!function_exists (hash_num)){ 
function hash_num($input) 
{ 
$hash = 5381; 
for ($i = 0; $i < strlen($str); $i++) 
{ 
$c = ord($str{$i}); 
$hash = (($hash << 5) + $hash) + $c; 
} 
return $hash; 
} 
} 
/**************** end *************************/ 
?> 

<?php 
/** 
* 防sql测试代码 
CREATE TABLE IF NOT EXISTS `tb` ( 
`id` int(10) unsigned NOT NULL auto_increment, 
`age` tinyint(3) unsigned NOT NULL, 
`name` char(100) NOT NULL, 
`note` text NOT NULL, 
PRIMARY KEY (`id`) 
) ENGINE=MyISAM DEFAULT CHARSET=utf8 ; 
**/ 
include_once('common.php'); 
var_dump(hash_num('dddd')); 
if(empty($_GET)) 
{ 
$_GET = array('age'=>'99','name'=>'a\'b\\\'c";','note'=>"a'b\'\nc#"); 
} 
$age = (int)$_GET['age']; 
$name = quote($_GET['name']); 
$note = quote($_GET['note']); 
$sql = "INSERT INTO `tb` ( `age`, `name`, `note`) VALUES 
( $age, $name, $note)"; 
var_dump($sql); 
?> 

<?php 
$magic_quotes_gpc = get_magic_quotes_gpc(); 
@extract(daddslashes($_COOKIE)); 
@extract(daddslashes($_POST)); 
@extract(daddslashes($_GET)); 
if(!$magic_quotes_gpc) { 
$_FILES = daddslashes($_FILES); 
} 

function daddslashes($string, $force = 0) { 
if(!$GLOBALS['magic_quotes_gpc'] || $force) { 
if(is_array($string)) { 
foreach($string as $key => $val) { 
$string[$key] = daddslashes($val, $force); 
} 
} else { 
$string = addslashes($string); 
} 
} 
return $string; 
} 
?> 

function inject_check($sql_str) { //防止注入 
$check = eregi('select|insert|update|delete|'|/*|*|../|./|union|into|load_file|outfile', $sql_str); 
if ($check) { 
echo "输入非法注入内容！"; 
exit (); 
} else { 
return $sql_str; 
} 
} 
function checkurl() { //检查来路 
if (preg_replace("/https教程?://([^:/]+).*/i", "1", $_server['http_referer']) !== preg_replace("/([^:]+).*/", "1", $_server['http_host'])) { 
header("location: http://s.jb51.net"); 
exit(); 
} 
} 
//调用 
checkurl(); 
$str = $_get['url']; 
inject_check($sql_str);//这条可以在获取参数时执行操作