C# JsonConvert

使用前先用json字符串转换出实体类

Root r = new Root();
r.lang = "zh-CN";
r.payload = new Payload();
r.payload.parm = new Params();
r.payload.parm.appKey = "--";
r.payload.parm.appSecret = "--";
string json = JsonConvert.SerializeObject(r);

Root rD =  JsonConvert.DeserializeObject<Root>(json);