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<?php $arr = array('11-01-2012', '01-01-2014', '01-01-2015', '09-02-2013', '01-01-2013'); function date_sort($a, $b) { return strtotime($a) - strtotime($b); } usort($arr, "date_sort"); print_r($arr);
Output for 5.1.3 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.28, 7.4.0 - 7.4.16, 8.0.0 - 8.0.3
Array ( [0] => 11-01-2012 [1] => 01-01-2013 [2] => 09-02-2013 [3] => 01-01-2014 [4] => 01-01-2015 )
Output for 5.1.0 - 5.1.2
Array ( [0] => 01-01-2013 [1] => 09-02-2013 [2] => 01-01-2015 [3] => 01-01-2014 [4] => 11-01-2012 )
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5
Array ( [0] => 01-01-2013 [1] => 01-01-2014 [2] => 01-01-2015 [3] => 09-02-2013 [4] => 11-01-2012 )