Calendar::isWorkTime

public function isWorkTime(DateTime $date)
{
	if ($this->isWeekend($date) || $this->isHoliday($date))
	{
		return false;
	}

	$isWorkTime = null;
	$cb = function (DateTime $start, DateTime $end) use(&$isWorkTime, $date)
	{
		$isWorkTime = $date->checkGT($start, false) && $date->checkLT($end, false);
		return false;
	};

	$this->processEachDay($date, null, true, $cb);

	return $isWorkTime;
}