JSON.NET JToken / Url encode with JSON.NET

Json.NET (Newtonsoft.Json) の基本的な使い方 | @Subaru

www.newtonsoft.com

JSON.NETでシリアライズした文字列のJSON ValueにURLエンコードを掛けたいので、以下のようにしました。
回帰的になってませんが・・・

        private class Test
        {
            public DateTime DT { get; set; }
            public int IT { get; set; }

            public string ST { get; set; }
        }

            Test a = new Test
            {
                DT = DateTime.Now,
                IT = 11431413,
                ST = "as$#121da+asa"
            };

            Test b = new Test
            {
                DT = DateTime.Now,
                IT = 11431413,
                ST = "asda!41fsf,asa"
            };

            List<Test> tests = new List<Test>{a,b};

            var jsonStr = JsonConvert.SerializeObject(a);
            var arrayJsonStr = JsonConvert.SerializeObject(tests);

            JObject aaa = JObject.Parse(jsonStr);
            JArray aaaList = JArray.Parse(arrayJsonStr);

            foreach (KeyValuePair<string, JToken> keyValuePair in aaa)
            {
                aaa[keyValuePair.Key] = HttpUtility.UrlEncode((string) aaa[keyValuePair.Key]);
            }

            foreach (JObject token in aaaList)
            {
                foreach (KeyValuePair<string, JToken> keyValuePair in token)
                {
                    token[keyValuePair.Key] = HttpUtility.UrlEncode((string)token[keyValuePair.Key]);
                }
            }

Thanks!