php formatting date and time formatting examples to share

//  Formatted date 
 static function formatDate($format, $datetime, $week = 0) {
     $datetime = $datetime > 3000 ? $datetime : strtotime($datetime);
     if ($week) {
         $weeknames = [
             ' day ',
             '1',
             '2',
             '3',
             '4',
             '5',
             '6'
         ];
         $format = str_replace('w', $weeknames [date('w', $datetime)], $format);
     }
     return date($format, $datetime);
 }

echo " weeks " . formatDate("w","2012-11-03 00:46:22" , 1) . " " . formatDate("Y-m-d", "2012-11-03 00:46:22");
echo " weeks " . formatDate("w","1388678400" , 1) . " " . formatDate("Y-m-d", "1388678400");
 weeks 6 2012-11-03
 weeks 5 2014-01-03