calendar-bundle/src/Resources/contao/dca/tl_module.php
public function getCalendars()
	{
		if (!$this->User->isAdmin && !\is_array($this->User->calendars))
		{
			return array();
		}

		$arrCalendars = array();
		$objCalendars = $this->Database->execute("SELECT id, title FROM tl_calendar ORDER BY title");

		while ($objCalendars->next())
		{
			if ($this->User->hasAccess($objCalendars->id, 'calendars'))
			{
				$arrCalendars[$objCalendars->id] = $objCalendars->title;
			}
		}

		return $arrCalendars;
	}
public function getCalendars()
	{
		if (!$this->User->isAdmin && !\is_array($this->User->calendars))
		{
			return array();
		}

		$arrCalendars = array();
		$objCalendars = $this->Database->execute("SELECT id, title FROM tl_calendar ORDER BY title");

		while ($objCalendars->next())
		{
			if ($this->User->hasAccess($objCalendars->id, 'calendars'))
			{
				$arrCalendars[$objCalendars->id] = $objCalendars->title;
			}
		}

		return $arrCalendars;
	}
Get all calendars and return them as array

@return array