如何按开始日期订购谷歌日历提要

如何按开始日期订购Google日历提要，哪个日期比现在更快？我尝试了很多不同的方法，但没有发生。我认为 API 中有一些功能，但我无法让它们工作。对不起，我的英语不好！

这是我的代码

'

    function outputCalendar($client)
    {
    $gdataCal = new Zend_Gdata_Calendar($client);
    $eventFeed = $gdataCal->getCalendarEventFeed();


    $d = 0;
    foreach ($eventFeed as $event):
    $event->id->text = str_replace ("http://www.google.com/calendar/feeds/default/private/full/", "", $event->id->text);

      $descrEvent = $event->getContent();

    if(mb_strlen($descrEvent, "UTF-8") > 200)
        $descrEvent = mb_substr($descrEvent, 0, 200, "UTF-8")."...";          
    ?>

    <div class="slider-container">
    <span style="font-weight: bold;"><?= stripslashes($event->title->text); ?></span><br />
    <span class="st">Start date: <?= date('Y-m-d', strtotime($event->when['0']->startTime)); ?></span> 
    <span class="et">End date: <?= date('Y-m-d', strtotime($event->when['0']->endTime)); ?></span>
    <span class="st"><?= stripslashes($event->where['0']->valueString); ?></span><br />
    <span class="str"><?= stripslashes($descrEvent); ?></span>
    </div>
    <? 
    $d++;

    endforeach; 
    }

    require_once 'Zend/Loader.php';
    Zend_Loader::loadClass('Zend_Gdata');
    Zend_Loader::loadClass('Zend_Gdata_AuthSub');
    Zend_Loader::loadClass('Zend_Gdata_ClientLogin');
    Zend_Loader::loadClass('Zend_Gdata_Calendar');

    $user = 'killerskunk@gmail.com';
    $pass = 'mr_bean';
    $service = Zend_Gdata_Calendar::AUTH_SERVICE_NAME; // predefined service name for calendar

    $client = Zend_Gdata_ClientLogin::getHttpClient($user,$pass,$service);

    outputCalendar($client);
    ?>`