How to set array first element dynamically with php

Question

I have a php array as follows,

<?php
    $arr = array('op'=>'pqr', 'ab'=>'xyz', 'mn'=>'abcd');

?>

How to set xyz value as first element with minimum loop,if the value exist.

Expected Result

<?php
    $arr = array('ab'=>'xyz', 'op'=>'pqr','mn'=>'abcd');
?>

@notme, alfasin is correct, but I might suggest that if you require order in this array, that you consider storing your data in a different manner. You can have an array of arrays, for example. — Brad
– Brad, Commented Jul 5, 2012 at 6:04

deceze · Accepted Answer · 2012-07-05 06:14:45Z

4

$ab = $array['ab'];
unset($array['ab']);
$array = array('ab' => $ab) + $array;

If the key itself is unknown, find it first:

$key = array_search('xyz', $array);
$tmp = $array[$key];
unset($array[$key]);
$array = array($key => $tmp) + $array;

Or go with a sort:

uasort($array, function ($a, $b) {
    if ($a == 'xyz') return -1;
    if ($b == 'xyz') return 1;
    return 0;
});

answered Jul 5, 2012 at 6:08

deceze♦

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Comments

Vimalnath · Accepted Answer · 2012-07-05 06:09:04Z

-2

<?php
    $arr = array('op'=>'pqr', 'ab'=>'xyz', 'mn'=>'abcd');
    ksort($arr);
    echo '<pre>';
    print_r($arr);

answered Jul 5, 2012 at 6:09

Vimalnath

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This won't give the result that OP is trying to get, it'll sort the array by key.