心跳可不可以把当前时时的时间戳发给客户端啊

$gateway = new Gateway('...');
$gateway->pingInterval = 10;
$gateway->pingNotResponseLimit = 1;
$gateway->pingData = new PingData;
class PingData 
{
    public function __toString()
    {
        return json_encode(array('type'=>'ping', 'time'=>time()));
    }
}