array
(
    [1] => array
        (
            [cat_id] => 1
            [cat_name] => other
        )
[2827511014] => array
        (
            [cat_id] => 2827511014
            [cat_name] => mobile phone housing
        )
[2827513014] => array
        (
            [cat_id] => 2827513014
            [cat_name] => mobile phone other accessories
        )
[2827516014] => array
        (
            [cat_id] => 2827516014
            [cat_name] => pc accessories
        )
[2827518014] => array
        (
            [cat_id] => 2827518014
            [cat_name] => electronics
        )
[3089502014] => array
        (
            [cat_id] => 3089502014
            [cat_name] => jewelry accessories
            [child] => array
                (
                    [3089509014] => array
                        (
                            [cat_id] => 3089509014
                            [cat_name] => necklace
                        )
[3089510014] => array
                        (
                            [cat_id] => 3089510014
                            [cat_name] => earrings
                        )
[3158873014] => array
                        (
                            [cat_id] => 3158873014
                            [cat_name] => headband
                        )
)
)
。。。。。。
回复讨论(解决方案) $a = 你的数组；foreach($a as $r) $b[] = $r['cat_name'];array_multisort($b, $a);