php - Sort multidimensional array by keys - fails on duplicates -

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• sort multi-dimensional array specific key 5 answers

i have function sortby() use sort multidimensional arrays particular key. here sample array:

array ( [0] => array     (         [id] => 4         [type] => 1         [game] => 1         [platform] => 0         [totalpot] => 7550     )  [1] => array     (         [id] => 5         [type] => 0         [game] => 2         [platform] => 0         [totalpot] => 7500     )  ) 

here function

function sortby($arr, $field='id', $order=1) {     $a = array();     if ( !is_array($arr) )         return false;     foreach($arr $subarr) {         $a[$subarr[$field]] = $subarr;     }      if ( $order == 1 ) sort($a);     else rsort($a);      return $a; } 

in case, calling sortby($array, 'totalpot'); work fine, because 2 values totalpot different. however, if run example , set both totalpot fields $7500, overwrites first occurrence latter.

what best way make function allow 2 items same value still keep them in relevant order? thought adding character, a or 1 end, seems sloppy , not predictable, better course of action appreciated.

you can simplify code , use usort(), e.g.

function sortarraybyfield(array &$arr, $field = "id", $asc = true) {     usort($arr, function($a, $b)use($field, $asc){         if($a[$field] == $b[$field])             return 0;         return $a[$field] > $b[$field] ? $asc : !$asc;     }); } 

then call this:

sortarraybyfield($array, "totalpot", true); print_r($array);