How to change orders of array?

Question

$a = array(0=>\'a\',1=>\'b\',2=>\'c\', 3=>\'d\');

I want to change the order to be 3,2,0,1：

$a = array(3=>\         


        

Answer 1

function reorder_array(&$array, $new_order) {
  $inverted = array_flip($new_order);
  uksort($array, function($a, $b) use ($inverted) {
    return $inverted[$a] > $inverted[$b];
  });
}

$a = array(0=>'a',1=>'b',2=>'c', 3=>'d');
reorder_array($a, array(3, 2, 0, 1));

var_dump($a);

Result:

Array ( [3] => d [2] => c [0] => a [1] => b )