php中将SimpleXMLElement Object数组转化为普通数组

$postStr = '<xml> <ToUserName><![CDATA[toUser]]></ToUserName> <FromUserName><![CDATA[fromUser]]></FromUserName>  <CreateTime>1348831860</CreateTime> <MsgType><![CDATA[text]]></MsgType> <Content><![CDATA[this is a test]]></Content> <MsgId>1234567890123456</MsgId> </xml>';$postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);$jsonStr = json_encode($postObj);$jsonArray = json_decode($jsonStr,true);print_r($jsonArray);

Array(    [ToUserName] => toUser    [FromUserName] => fromUser    [CreateTime] => 1348831860    [MsgType] => text    [Content] => this is a test    [MsgId] => 1234567890123456)