当用户浏览某页面时需要转向到注册页面,注册完成后希望用户能返回到之前想访问的页面,这个类或许有用,目前该类还在完善中.
<?php /* * @author badboy * @2009-5-27 * @php4 类语法 * 类Tracker用于跟踪用户访问页面 * 页面信息存放于Cookie中,如果Cookie被禁用,此类将不起作用. */ class Tracker { var $max_pages = 10 ; //最多保留多少个页面信息 var $trackStack; //踪迹栈 var $cookieName; //cookie名称,默认为 $_SERVER['HTTP_HOST'].'_PAGE_TRACK' /* * 构造方法 */ function Tracker() { $this->trackStack=array(); $this->cookieName = '_PAGE_TRACK'; $this->loadFromCookie(); //移除过多的页面 if(count($this->trackStack)>$this->max_pages) { for($i=0;$i<count($this->trackStack)-$this->max_pages;$i++) { array_shift($this->trackStack); } } } /* * 将页面信息保存到记录栈中,此方法被重截. * 无参数版本表示将当前页加到踪迹栈中 * 有参数版本表示将指定页加到踪迹栈中 */ function addPage() { $num_args = func_num_args(); $arr_args = func_get_args(); switch($num_args) { case 0: $this->addPageOverloading_1(); break; case 1: $this->addPageOverloading_2($arr_args[0]); break; } } function addPageOverloading_1() { $page = urlencode($_SERVER['SCRIPT_NAME'].'?'.$_SERVER['QUERY_STRING']); if($page!=$this->trackStack[count($this->trackStack)-1]) { $this->trackStack[]=$page; } $this->mapToCookie(); } function addPageOverloading_2($page) { $page = urlencode($page); if($page!=$this->trackStack[count($this->trackStack)-1]) { $this->trackStack[]=$page; } $this->mapToCookie(); } /* * 清除记录 */ function clear() { $this->trackStack=array(); $this->mapToCookie(); } function mapToCookie() { $cookies = implode('|||',$this->trackStack); setcookie($this->cookieName,$cookies); } /* * 从Cookie读取页面记录到$trackStack; * 它们以|||分隔 */ function loadFromCookie() { $cookies = $_COOKIE[$this->cookieName]; if(!$cookies) return; $this->trackStack = explode('|||',$cookies); } /* * 返回栈中的页面 * 参数-1表示返回倒数一个页面,-2表示倒数第2个页面,0或空表示返回栈底的页面 * 此方法被重载 */ function getPage() { $num_args = func_num_args(); $arr_args = func_get_args(); switch($num_args) { case 0: return $this->getPageOverloading_1(); break; case 1: return $this->getPageOverloading_2($arr_args[0]); break; } } function getPageOverloading_1() { return urldecode($this->trackStack[0]); } function getPageOverloading_2($position) { if($position==0) { return $this->getPageOverloading_1(); } else { return urldecode($this->trackStack[count($this->trackStack)+$position]); } } } ?>
