PHP: custom date time format

customDateTime.php

<?php 	
	/**
	 * The function convert an input string to a date with desired format.
	 * @param  string $date
	 * @param  string $format
	 * @return datetime
	 */
	function customDate($date,$format)
	{
		if($date=="" || $date=="0000-00-00 00:00:00")
			return 0;
		return date_format(new DateTime($date),$format);
	}
?>