求教一个数组问题

<code>   $simiArray = [];
    foreach($resourceArray as $rVal) {
        $order_sn = $rVal['order_sn'];
        $simiArray[$rVal['order_sn']]['order_sn'] = $rVal['order_sn'];
        $simiArray[$order_sn]['order_add_time'] = $rVal['order_add_time'];
        $simiArray[$rVal['order_sn']]['pay_amonut'] = $rVal['pay_amonut'];
        unset($rVal['order_sn']);
        unset($rVal['order_add_time']);
        unset($rVal['pay_amonut']);
        $simiArray[$order_sn]['order_detail'][] = $rVal;
    }
</code>