请教以下XML字符串要怎么解析得到code和result呢

$xml = '

  0
  短信提交成功
';

$xml = iconv('gbk', 'utf-8', $xml);//转了也不行

$dom = simplexml_load_string($xml);

$result_code = iconv('utf-8', 'gbk', $dom->code);//结果代码
$result_info = iconv('utf-8', 'gbk', $dom->result);//结果信息