_pdo = $pdo; $this->_ip = !empty($_SERVER['REMOTE_ADDR']) ? $_SERVER['REMOTE_ADDR'] : null; $this->_maxLifeTime = ini_get('session.gc_maxlifetime'); } public function open($path,$name) { return true; } public function close() { return true; } public function read($id) { $sql = 'SELECT * FROM session where PHPSESSID = ?'; $stmt = $this->_pdo->prepare($sql); $stmt->execute(array($id)); if (!$result = $stmt->fetch(PDO::FETCH_ASSOC)) { return null; } elseif ($this->_ip != $result['client_ip']) { return null; } elseif ($result['update_time']+$this->_maxLifeTime < time()){ $this->destroy($id); return null; } else { return $result['data']; } } public function write($id,$data) { $sql = 'SELECT * FROM session where PHPSESSID = ?'; $stmt = $this->_pdo->prepare($sql); $stmt->execute(array($id)); if ($result = $stmt->fetch(PDO::FETCH_ASSOC)) { if ($result['data'] != $data) { $sql = 'UPDATE session SET update_time =? , date = ? WHERE PHPSESSID = ?'; $stmt = $this->_pdo->prepare($sql); $stmt->execute(array(time(), $data, $id)); } } else { if (!empty($data)) { $sql = 'INSERT INTO session (PHPSESSID, update_time, client_ip, data) VALUES (?,?,?,?)'; $stmt = $this->_pdo->prepare($sql); $stmt->execute(array($id, time(), $this->_ip, $data)); } } return true; } public function destroy($id) { $sql = 'DELETE FROM session WHERE PHPSESSID = ?'; $stmt = $this->_pdo->prepare($sql); $stmt->execute(array($id)); return true; } public function gc($maxLifeTime) { $sql = 'DELETE FROM session WHERE update_time < ?'; $stmt = $this->_pdo->prepare($sql); $stmt->execute(array(time() - $maxLifeTime)); return true; } } try{ $pdo = new PDO('mysql:host=localhost;dbname=rphp4zf', 'root','rickyfeng'); $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); new SessionToDB($pdo); } catch(PDOException $e) { echo 'Error: '.$e->getMessage(); }来源：豆芽博客,地址：http://www.aichengxu.com/article/PHP/567_1.html保留原文链接,是开源分享的开始.