PHP将session信息存储到数据库的类实例

PHP将session信息存储到数据库的类实例

本文实例讲述了PHP将session信息存储到数据库的类。分享给大家供大家参考。具体分析如下：

SessionHandlerInterface接口是PHP内置的接口，直接实现就行了
具体可以看php手册关于session_set_save_handler函数的解释！

PHP代码如下：

代码如下:

/**
* session信息存储到数据库的类
* 表结构：
* CREATE TABLE IF NOT EXISTS `sessioninfo` (
* `sid` varchar(255) NOT NULL,
* `value` text NOT NULL,
* `expiration` timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
* PRIMARY KEY (`sid`)
* ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
*/
class MySessionHandler implements SessionHandlerInterface {
/**
* @access private
* @var object 数据库连接
*/
private $_dbLink;
/**
* @access private
* @var string 保存session的表名
*/
Private $_sessionTable;
/**
* @access private
* @var string session名
*/
private $_sessionName;
/**
* @const 过期时间
*/
const SESSION_EXPIRE = 10;
public function __construct($dbLink, $sessionTable) {
if(!is_object($dbLink)) {
return false;
}
$this->_dbLink = $dbLink;
$this->_sessionTable = $sessionTable;
}
/**
* 打开
* @access public
* @param string $session_save_path 保存session的路径
* @param string $session_name session名
* @return integer
*/
public function open($session_save_path, $session_name) {
$this->_sessionName = $session_name;
return 0;
}
/**
* 关闭
* @access public
* @return integer
*/
public function close() {
return 0;
}
/**
* 关闭session
* @access public
* @param string $session_id session ID
* @return string
*/
public function read($session_id) {
$query = "SELECT value FROM {$this->_sessionTable} WHERE sid = {$session_id} AND UNIX_TIMESTAMP(expiration) + " . self::SESSION_EXPIRE . " > UNIX_TIMESTAMP(NOW())";
$result = $this->_dbLink->query($query);
if(!isset($value) || empty($value)) {
$value = "";
return $value;
}
$this->_dbLink->query("UPDATE {$this->_sessionTable} SET expiration = CURRENT_TIMESTAMP() WHERE sid = {$session_id}");
$value = $result->fetch_array();
$result->free();
return $value['value'];
}
/**
* 写入session
* @access public
* @param string $session_id session ID
* @param string $session_data session data
* @return integer
*/
public function write($session_id, $session_data) {
$query = "SELECT value FROM {$this->_sessionTable} WHERE sid = '{$session_id}' AND UNIX_TIMESTAMP(expiration) + " . self::SESSION_EXPIRE . " > UNIX_TIMESTAMP(NOW())";
$result = $this->_dbLink->query($query);
$result = $result->fetch_array();
if(!empty($result)) {
$result = $this->_dbLink->query("UPDATE {$this->_sessionTable} SET value = {$session_data} WHERE sid = {$session_id}");
}
else{
$result = $this->_dbLink->query("INSERT INTO {$this->_sessionTable} (sid, value) VALUES ('{$session_id}', '{$session_data}')");
}
if($result){
return 0;
}
else{
return 1;
}
}
/**
* 销魂session
* @access public
* @param string $session_id session ID
* @return integer
*/
public function destroy($session_id) {
$result = $this->_dbLink->query("DELETE FROM {$this->_sessionTable} WHERE sid = '{$session_id}'");
if($result){
return 0;
}
else{
return 1;
}
}
/**
* 垃圾回收
* @access public
* @param string $maxlifetime session 最长生存时间
* @return integer
*/
public function gc($maxlifetime) {
$result = $this->_dbLink->query("DELETE FROM {$this->_sessionTable} WHERE UNIX_TIMESTAMP(expiration) < UNIX_TIMESTAMP(NOW()) - " . self::SESSION_EXPIRE);
if($result){
return 0;
}
else{
return 1;
}
}
}
$dbLink = new mysqli("localhost", "root", "root", "test");
$sessionTable = "sessioninfo";
$handler = new MySessionHandler($dbLink, $sessionTable);
session_set_save_handler($handler);
session_start();
$_SESSION['name'] = "test";
echo $_SESSION["name"];
//session_destroy();

希望本文所述对大家的php程序设计有所帮助。