PHP名称空间simplexml问题

通常，人们使用children（）。

$rss = simplexml_load_string(    '<?xml version="1.0" encoding="utf-8"?>    <rss version="2.0" xmlns:moshtix="http://www.moshtix.com.au">        <channel> <link>qweqwe</link> <moshtix:genre>asdasd</moshtix:genre>        </channel>    </rss>');foreach ($rss->channel as $channel){    echo 'link: ', $channel->link, "n";    echo 'genre: ', $channel->children('moshtix', true)->genre, "n";}