我试图将JSON输出转换为XML。不幸的是我得到这个错误：

JSON根对象具有多个属性。根对象必须具有单个属性才能创建有效的XML文档。考虑指定DeserializeRootElementName。

这就是我到目前为止所创建的。

string url = string.Format("https://graph.facebook.com/{0}?fields=posts.fields(message)&access_token={1}", user_name, access_token);

HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;

using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
{
    StreamReader reader = new StreamReader(response.GetResponseStream());
    jsonOutput = reader.ReadToEnd();
    Console.WriteLine("THIS IS JSON OUTPUT: " + jsonOutput);
}
XmlDocument doc = (XmlDocument)JsonConvert.DeserializeXmlNode(jsonOutput);
Console.WriteLine(doc);

这是我的JSON输出：

{"id":"108013515952807","posts":{"data":[{"id":"108013515952807_470186843068804","created_time":"2013-05-14T20:43:28+0000"},{"message":"TEKST","id":"108013515952807_470178529736302","created_time":"2013-05-14T20:22:07+0000"}

我怎么解决这个问题？