本文实例讲述了PHP封装的数据库保存session功能类。分享给大家供大家参考，具体如下：
PHP用数据库保存session类：
<?php
class SafeSessionHandler implements SessionHandlerInterface {
public $save_path;
public $session_name;
public $table;
public function __construct() {
$this->table = new Table("safe_session");
}
private function session_id_parse($session_id) {
$time = hexdec(substr($session_id, 0, 8));
$skey = substr($session_id, 8);
return array($time, $skey);
}
public function close() {
loginfo("close: ");
return true;
}
public function create_sid() {
loginfo("create_sid: ");
$time = time();
$skey = "";
$char = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
for ($i=0; $i<52; $i++) {
$skey .= $char{mt_rand(0, 61)};
}
$session = array(
"time" => $time,
"skey" => $skey,
"sval" => "",
);
$this->table->insert($session);
return dechex($time) . $skey;
}
public function destroy($session_id) {
loginfo("destroy: %s", $session_id);
list($time, $skey) = $this->session_id_parse($session_id);
$this->table->where("time = ?", $time)->where("skey = ?", $skey)->delete();
return true;
}
public function gc($maxlifetime) {
loginfo("gc: %s", $maxlifetime);
$this->table->where("time < ?", time() - 86400 * 30)->delete();
return true;
}
public function open($save_path, $session_name) {
loginfo("open: %s, %s", $save_path, $session_name);
$this->save_path = $save_path;
$this->session_name = $session_name;
return true;
}
public function read($session_id) {
loginfo("read: %s", $session_id);
list($time, $skey) = $this->session_id_parse($session_id);
$row = $this->table->where("time = ?", $time)->where("skey = ?", $skey)->select()->fetch();
if (empty($row)) {
return "";
}
return $row["sval"];
}
public function write($session_id, $session_data) {
loginfo("write: %s, %s", $session_id, $session_data);
$session = array("sval" => $session_data,);
list($time, $skey) = $this->session_id_parse($session_id);
$this->table->where("time = ?", $time)->where("skey = ?", $skey)->update($session);
return true;
}
}
希望本文所述对大家PHP程序设计有所帮助。