PHP独立Session数据库存储操作类分享(3)

/**
     * Sets a session variable and updates the change list.
     *
     * @param    string    Name of session variable to update
     * @param    string    Value to update it with
     */
    public function set($key, $value)
    {
        if ($this->_vars["$key"] != $value)
        {
            $this->_vars["$key"] = $value;
            $this->_changes["$key"] = true;
        }
    }

public function get($key)
    {
        return $this->_vars["$key"];
    }

public function unsetchangedvar($var)
    {
        if (isset($this->_changes["$var"]))
        {
                unset($this->_changes["$var"]);
        }
    }

/**
     * Fetches a valid sessionhash value, not necessarily the one tied to this session.
     *
     * @return    string    32-character sessionhash
     */
    static function fetch_sessionhash()
    {
        return hash(‘md5′ , TIMENOW . rand(1, 100000) . uniqid() );
    }

private function _init_config()
        {
                $registry = Zend_Registry::getInstance();
                $config = $registry->get(‘config');
                $this->_config[‘host'] = $config->database->params->host;
        $this->_config[‘port'] = $config->database->params->port;
        $this->_config[‘username'] = $config->database->params->username;
        $this->_config[‘password'] = $config->database->params->password;
        $this->_config[‘dbname'] = $config->database->params->dbname;
        $this->_config[‘tablename'] = $config->database->session->tablename;

}

/**
         * initialize database connection
         */
        public function init_db()
        {
            if ($this->_db_inited)
            {
                return true;
            }

//mysqli_report(MYSQLI_REPORT_OFF);

$this->_mysqli = new mysqli(
                $this->_config[‘host'],
                $this->_config[‘username'],
                $this->_config[‘password'],
                $this->_config[‘dbname'],
                $this->_config[‘port']
            );

/* check connection */
                if (mysqli_connect_errno())
                {

// printf("Connect failed: %sn", mysqli_connect_error());
                    // echo ‘in ‘, __FILE__, ‘ on line ‘, __LINE__;
                    echo "{ success: false, errors: { reason: ‘ Connect failed: " . addslashes( mysqli_connect_error() ) . "' }}";
                    exit();

}

$this->_mysqli->query(‘set names latin1′);
            $this->_db_inited = true;

return true;
        }