php实现的redis缓存类定义与使用方法示例

 host = "127.0.0.1"; $this->port = "6379"; $redis = new Redis(); $redis->pconnect($this->host,$this->port); $this->redis=$redis; $this->cacheid = $this->getcacheid(); $this->lifetime = $lifetime; $this->data=$redis->hMGet($this->cacheid, array('content','creattime')); //print_r($this->redis); //print_r($this->data); } /** * 检查缓存是否有效 */ private function isvalid(){ $data=$this->data; if (!$data['content']) return false; if (time() - $data['creattime'] > $this->lifetime) return false; return true; } /** * 写入缓存 * $mode == 0 , 以浏览器缓存的方式取得页面内容 */ public function write($mode=0,$content='') { switch ($mode) { case 0: $content = ob_get_contents(); break; default: break; } ob_end_flush(); try { $this->redis->hMset($this->cacheid, array('content'=>$content,'creattime'=>time())); $this->redis->expireAt($this->cacheid, time() + $this->lifetime); } catch (Exception $e) { $this->error('写入缓存失败!'); } } /** * 加载缓存 * exit() 载入缓存后终止原页面程序的执行,缓存无效则运行原页面程序生成缓存 * ob_start() 开启浏览器缓存用于在页面结尾处取得页面内容 */ public function load() { if ($this->isvalid()) { echo $this->data['content']; exit(); } else { ob_start(); } } /** * 清除缓存 */ public function clean() { try { $this->redis->hDel($this->cacheid, array('content','creattime')); } catch (Exception $e) { $this->error('清除缓存失败!'); } } /** * 取得缓存文件路径 */ private function getcacheid() { return $this->dir.md5($this->geturl()).$this->ext; } /** * 取得当前页面完整url */ private function geturl() { $url = ''; if (isset($_SERVER['REQUEST_URI'])) { $url = $_SERVER['REQUEST_URI']; } else { $url = $_SERVER['Php_SELF']; $url .= empty($_SERVER['QUERY_STRING'])?'':'?'.$_SERVER['QUERY_STRING']; } return $url; } /** * 输出错误信息 */ private function error($str) { echo '
'.$str.'
'; } } //用法： // require_once('redisCache.php'); // $cache = new redisCache(10); //设置缓存生存期 // if ($_GET['clearCache']) $cache->clean(); // else $cache->load(); //装载缓存,缓存有效则不执行以下页面代码 // //页面代码开始 // //页面代码结束 // $cache->write(); //首次运行或缓存过期,生成缓存 ?>