example:

页面:dl.php
--------------------------------------------------------------------------------------
复制代码 代码如下:
<?php

$id=$_GET['id'];
$act=$_GET['act'];

switch($act){
default:
case"display":displayHTML();break;
case"down":down();break;
}

functiondisplayHTML($id){
setcookie("visited","true");

//printyourHTML.
}

functiondown($id){
if(!isset($_COOKIE['visited']))print"你盗联?";

$sql="selectpathfromTABLEwhereid=".$id;
//..............................
}
?>

<ahref="dl.php?id=1&act=down">DownloadNow...</a>