如何用 php 抓取微信文章正文

$url = "http://mp.weixin.qq.com/s?__biz=MzA5NTQ2NjUzMA==&mid=207136729&idx=1&sn=a82af7b7ba0bee9a7017b607dc7e5d4b&scene=5#rd";
$contents = file_get_contents($url);
$contents = explode('js_article', $contents);
$contents = $contents[1];
$contents = explode('