用 MySQL 来记录 Session 数据实例

MySqlSessionHandlerExample.php

<?php
ob_end_clean();
if((int)ini_get('session.auto_start') > 0)
{
	ini_set('session.auto_start',0);
}

class MySqlSessionHandler implements SessionHandlerInterface
{
	private $_db;

	public function close()
	{
		return $this->_db->close();
	}

	public function destroy($sessionn_id)
	{
		$sql = 'delete from sessions where session_id="'.$session_id.'"';
		$this->_db->query($sql);
		$_SESSION = array();
		return TRUE;
	}

	public function gc($maxlifetime)
	{
		$sql = 'delete from sessions where expire < '.time();
		$zen_session_db->query($sql);
		return TRUE;
	}

	public function open($save_path, $name)
	{
		$this->_db = new mysqli('localhost','root','password','test');
		return (boolean)$this->_db;
	}

	public function read($session_id)
	{
		$sql = 'select session_value from sessions where session_id="'.$session_id.'"';
		$query = $this->_db->query($sql);
		if($this->_db->errno) {
			die($this->_db->error);
		}
		if($query -> num_rows == 1) {
			$session_data = $query->fetch_assoc();
			return $session_data['session_value'];
		} else {
			return "";
		}
	}

	public function write($session_id, $session_data)
	{
		$sql = 'select count(*) as count from sessions where session_id="'.$session_id.'"';
		$query = $this->_db->query($sql);
		$result = $query->fetch_assoc();
		if($this->_db->errno) {
			die($this->_db->error);
		}
		if($result['count'] > 0)
		{
			$sql = 'update sessions set session_value=\''.$session_data.'\',expire='.(time()+60*60).' where session_id="'.
				$session_id.'"';
			$this->_db->query($sql);
		} else {
			$sql = 'insert into sessions values("'.$session_id.'","'.(time()+60*60).'",\''.$session_data.'\')';
			$this->_db->query($sql);
		}
		if($this->_db->affected_rows > 0) {
			return TRUE;
		} else {
			return FALSE;
		}
	}
}

$handler = new MySqlSessionHandler;
session_set_save_handler($handler, true);

session_name('zenID');
session_start();
$_SESSION['age'] = 17;
$_SESSION['color'] = 'green';
$_SESSION['color2'] = 'red';