recursion - PHP - multidimensional array to query string

Question

Searched for so long but didn't get any feasible answer.

A) Input:

$array = array(
            'order_source' => array('google','facebook'), 
            'order_medium' => 'google-text'
          );

Which looks like:

Array
(
    [order_source] => Array
        (
            [0] => google
            [1] => facebook
        )

    [order_medium] => google-text
)

B) Required output:

order_source=google&order_source=facebook&order_medium=google-text

C) What I've tried (http://3v4l.org/b3OYo):

$arr = array('order_source' => array('google','facebook'), 'order_medium' => 'google-text');

function bqs($array, $qs='')
{
    foreach($array as $par => $val)
    {
        if(is_array($val))
        {
            bqs($val, $qs);       
        }
        else
        {
           $qs .= $par.'='.$val.'&';
        }
    }
    return $qs;
}

echo $qss = bqs($arr);

D) What I'm getting:

order_medium=google-text&

Note: It should also work for any single dimensional array like http_build_query() works.

Answer 1

I hope that this is what you are looking for, it works with single to n-dimensinal arrays.

$walk = function( $item, $key, $parent_key = '' ) use ( &$output, &$walk ) {

    is_array( $item ) 
        ? array_walk( $item, $walk, $key ) 
        : $output[] = http_build_query( array( $parent_key ?: $key => $item ) );

};

array_walk( $array, $walk );

echo implode( '&', $output );  // order_source=google&order_source=facebook&order_medium=google-text