Moving array element to top in PHP

Question

$arr = array(
    'a1'=>'1',
    'a2'=>'2'
);

I need to move the a2 to the top, as well as keep the a2 as a key how would I go on about it I can't seem to think a way without messing something up :)

Answer 1

try this:

$key = 'a3';
$arr = [
    'a1' => '1',
    'a2' => '2',
    'a3' => '3',
    'a4' => '4',
    'a5' => '5',
    'a6' => '6'
];
if (isset($arr[ $key ]))
    $arr = [ $key => $arr[ $key ] ] + $arr;

result:

array(
    'a3' => '3',
    'a1' => '1',
    'a2' => '2',
    'a4' => '4',
    'a5' => '5',
    'a6' => '6'
)