C#结构josn格式

C#构造josn格式
 {
           "touser":"OPENID",
           "template_id":"ngqIpbwh8bUfcSsECmogfXcV14J0tQlEpBO27izEYtY",
           "url":"http://weixin.qq.com/download",
           "topcolor":"#FF0000",
           "data":{
                   "first": {
                       "value":"恭喜你购买成功！",
                       "color":"#173177"
                   },
                   "keynote1":{
                       "value":"巧克力",
                       "color":"#173177"
                   },
                   "keynote2": {
                       "value":"39.8元",
                       "color":"#173177"
                   },
                   "keynote3": {
                       "value":"2014年9月16日",
                       "color":"#173177"
                   },
                   "remark":{
                       "value":"欢迎再次购买！",
                       "color":"#173177"
                   }
           }
       }
这样如何用C#构造出一个josn格式
------解决思路----------------------

  public class JsonHelper
    {

        /// <summary>
        /// JSON序列化(二进制方式，实体类使用[Serializable])
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="t"></param>
        /// <returns></returns>
        public static string JsonSerializerIO<T>(T t)
        {
            DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
            using (MemoryStream ms = new MemoryStream())
            {
                ser.WriteObject(ms, t);
                string jsonString = Encoding.UTF8.GetString(ms.ToArray());
                ms.Close();
                return jsonString;
            }
        }

        /// <summary>
        /// JSON反序列化(二进制方法，实体类使用[Serializable])
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="jsonString"></param>
        /// <returns></returns>
        public static T JsonDeserializeIO<T>(string jsonString)
        {
            DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
            using (MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonString)))
            {
                T obj = (T)ser.ReadObject(ms);
                return obj;
            }
        }