function calendar_to_ical($calendar)
{
$vCalendar = new \Eluceo\iCal\Component\Calendar('Calendar API V1');
$vCalendar->setName($calendar->summary);
$vCalendar->setDescription($calendar->description);
$vCalendar->setTimezone($calendar->timezone);
return $vCalendar;
}
$vTimezoneRuleDst->setRecurrenceRule($dstRecurrenceRule);
// 3. Create timezone rule object for Standard Time
$vTimezoneRuleStd = new \Eluceo\iCal\Component\TimezoneRule(\Eluceo\iCal\Component\TimezoneRule::TYPE_STANDARD);
$vTimezoneRuleStd->setTzName('CET');
$vTimezoneRuleStd->setDtStart(new \DateTime('1996-10-27 03:00:00', $dtz));
$vTimezoneRuleStd->setTzOffsetFrom('+0200');
$vTimezoneRuleStd->setTzOffsetTo('+0100');
$stdRecurrenceRule = new \Eluceo\iCal\Property\Event\RecurrenceRule();
$stdRecurrenceRule->setFreq(\Eluceo\iCal\Property\Event\RecurrenceRule::FREQ_YEARLY);
$stdRecurrenceRule->setByMonth(10);
$stdRecurrenceRule->setByDay('-1SU');
$vTimezoneRuleStd->setRecurrenceRule($stdRecurrenceRule);
// 4. Create timezone definition and add rules
$vTimezone = new \Eluceo\iCal\Component\Timezone($tz);
$vTimezone->addComponent($vTimezoneRuleDst);
$vTimezone->addComponent($vTimezoneRuleStd);
$vCalendar->setTimezone($vTimezone);
// 5. Create an event
$vEvent = new \Eluceo\iCal\Component\Event();
$vEvent->setDtStart(new \DateTime('2012-12-24', $dtz));
$vEvent->setDtEnd(new \DateTime('2012-12-24', $dtz));
$vEvent->setSummary('Summary with some german "umlauten" and a backslash \\: Kinder mögen Äpfel pflücken.');
// 6. Adding Timezone
$vEvent->setUseTimezone(true);
// 7. Add event to calendar
$vCalendar->addComponent($vEvent);
// 8. Set headers
header('Content-Type: text/calendar; charset=utf-8');
header('Content-Disposition: attachment; filename="cal.ics"');
// 9. Output
echo $vCalendar->render();
