Question

I tried to search and found this:

Sort an array by a child array's value in PHP

But the function does not work in my case:

                $sorted = array();
                foreach($players as $player)
                {
                    $p = Model::factory('user');
                    $p->load($player['id']);

                    $sorted[] = array('id' => $player['id'], 'username' => $p->get_username());
                }

How can i sort the array alphabetic after the username?

The function,

function cmp($a, $b) {
        if ($a['username'] == $b['username']) {
                return 0;
        }
        return ($a['username'] < $b['username']) ? -1 : 1;
}

and then calling usort($sorted,”cmp”); will not work out for me (getting error undefined index[2])..

And is there any way to choose whether it should be sorting descending or ascending?

Answer 1

The ‘cmp’ function will be:

// $param - the parameter by which you want to search
function cmp(&$a, &$b, $param) {
    switch( $param ) {
        case 'id':
            if ( $a['id'] == $b['id'] ) {
                return 0;
            }

            return ( $a['id'] < $b['id'] ) ? -1 : 1;
            break;
        case 'username':
            // string comparison
            return strcmp($a['username'], $b['username']);
            break;
    }
}

// this is the sorting function by using an anonymous function
// it is needed to pass the sorting criterion (sort by id / username )
usort( $sorted, function( $a,$b ) {
    return cmp( $a, $b, 'username');
});