方式一使用 JavaScriptSerializer

var serializer = new JavaScriptSerializer();
var obj = serializer.Deserialize<Dictionary<string, string>>(data);

string accessToken;
if (!obj.TryGetValue("access_token", out accessToken))
{
　　
}
var opentid = obj["openid"];

方式二 使用 JObject 需要下载 Newtonsoft.Json

JObject jo = (JObject)JsonConvert.DeserializeObject(result);
result = jo.GetValue("token").ToString();

 处理null 问题

JsonConvert.DeserializeObject<orderinfo>(strjson, new JsonSerializerSettings { NullValueHandling = NullValueHandling.Ignore })

   JArray jArray = JArray.Parse(item);
            foreach (JToken jToken in jArray)
            {
                var job = (JObject)jToken;
                if (job["item_size"].Value<int>() == 0)