使用session_set_save_handler()函數，將Session的內容寫入數據庫
1 <?php
2 /*
3 *@author Fahy
4 *@link http://home.cnblogs.com/u/HuangWj
5 *數據庫為mysql，
6 *數據庫名為session，表名為session，
7 *表中字段包括PHPSESSID,update_time,client_ip,data
8 */
9 class Session{
10 private static $handler = null;
11 private static $ip = null;
12 private static $lifetime = null;
13 private static $time = null;
14
15 //配置靜態變量
16 private static function init($handler){
17 self::$handler = $handler; //獲取數據庫資源
18 self::$ip = !empty($_SERVER["REMOTE_ADDR"])? $_SERVER["REMOTE_ADDR"]:'unkonw'; //獲取客戶端ip
19 self::$lifetime = ini_get('session.gc_maxlifetime'); //獲取session生命周期
20 self::$time = time(); //獲取當前時間
21 }
22 //調用session_set_save_handler()函數並開啟session
23 static function start($pdo){
24 self::init($pdo);
25 session_set_save_handler(
26 array(__CLASS__,'open'),
27 array(__CLASS__,'close'),
28 array(__CLASS__,'read'),
29 array(__CLASS__,'write'),
30 array(__CLASS__,'destroy'),
31 array(__CLASS__,'gc')
32 );
33 session_start();
34 }
35
36 public static function open($path,$name){
37 return true;
38 }
39 public static function close(){
40 return true;
41 }
42
43 //查詢數據庫中的數據
44 public static function read($PHPSESSID){
45 $sql = "select PHPSESSID,update_time,client_ip,data from session where PHPSESSID=?";
46 $stmt = self::$handler->prepare($sql);
47 $stmt->execute(array($PHPSESSID));
48 if(!$result = $stmt->fetch(PDO::FETCH_ASSOC)){
49 return '';
50 }
51 if(self::$ip == $result['client_ip']){
52 self::destroy($PHPSESSID);
53 return '';
54 }
55 if(($result['update_time']+self::$lifetime)<self::$time){
56 self::destroy($PHPSESSID);
57 return '';
58 }
59 return $result['data'];
60 }
61 /*
62 *首先查詢該session是否存在數據，如果存在，則更新數據，如果不存在，則插入數據
63 */
64 //將session寫入數據庫中，$data傳入session中的keys和values數組
65 public static function write($PHPSESSID,$data){
66 $sql = "select PHPSESSID,update_time,client_ip,data from session where PHPSESSID=?";
67 $stmt = self::$handler->prepare($sql);
68 $stmt->execute(array($PHPSESSID));
69
70 if($result=$stmt->fetch(PDO::FETCH_ASSOC)){
71 if($result['data'] != $data || self::$time > ($result['update_time']+30)){
72 $sql = "update session set update_time=?,data=? where PHPSESSID = ?";
73 $stmt = self::$handler->prepare($sql);
74 $stmt->execute(array($self::$time,$data,$PHPSESSID));
75 }
76 }else{
77 if(!empty($data)){
78 try{
79 $sql = "insert into session(PHPSESSID,update_time,client_ip,data) values(?,?,?,?)";
80 }catch(PDOException $e){
81 echo $e->getMessage();
82 }
83 $sth = self::$handler->prepare($sql);
84 $sth->execute(array($PHPSESSID,self::$time,self::$ip,$data));
85 }
86 }
87 return true;
88 }
89
90 public static function destroy($PHPSESSID){
91 $sql = "delete from session where PHPSESSID = ?";
92 $stmt = self::$handler->prepare($sql);
93 $stmt->execute(array($PHPSESSID));
94 return true;
95 }
96 public static function gc($lifetime){
97 $sql = "delete from session where update_time<?";
98 $stmt = self::$handler->prepare($sql);
99 $stmt->execute(array(self::$time-$lifetime));
100 return true;
101 }
102 }
103 //使用PDO連接數據庫
104 try{
105 $pdo = new PDO("mysql:host=localhost;dbname=session","root","hwj193");
106 }catch(PDOException $e){
107 echo $e->getMessage();
108 }
109 //傳遞數據庫資源
110 Session::start($pdo);
