json serialization and deserialization C# class

public static class JsonSerializer  
    {  
        private static ITracing _tracing = TracingManager.GetTracing(typeof(JsonSerializer));  
   
   
        /// <summary>  
        /// 将指定对象序列化为 JavaScript 对象表示法 (JSON) 数据，并将生成的 JSON 写入流中。  
        /// </summary>  
        /// <typeparam name="T">对象类型</typeparam>  
        /// <param name="stream">流对象</param>  
        /// <param name="obj">序列化对象</param>  
        public static void Serialize<T>(Stream stream, T obj)  
        {  
            JsonSerializeProxy<T>.Default.Serialize(stream, obj);  
        }  
   
   
        /// <summary>  
        /// 将指定对象序列化为 JavaScript 对象表示法 (JSON) 数据，并返回对应的字符串。  
        /// </summary>  
        /// <typeparam name="T">对象类型</typeparam>  
        /// <param name="obj">序列化对象</param>  
        /// <returns>JavaScript 对象表示法 (JSON) 字符串</returns>  
        public static string Serialize<T>(T obj)  
        {  
            using (MemoryStream ms = new MemoryStream())  
            {  
                JsonSerializeProxy<T>.Default.Serialize(ms, obj);  
   
   
                string jsonStr = Encoding.UTF8.GetString(ms.ToArray());  
   
   
                _tracing.InfoFmt("{0} json serialize result: {1}", typeof(T).ToString(), jsonStr);  
   
   
                return jsonStr;  
            }  
        }  
   
   
        public static T DeSerialize<T>(string jsonStr)  
        {  
            return JsonSerializeProxy<T>.Default.DeSerialize(jsonStr);  
        }  
    }  
   
   
    public class JsonSerializeProxy<T>  
    {  
        private static readonly JsonSerializeProxy<T> _default = new JsonSerializeProxy<T>();  
        private DataContractJsonSerializer _serializer;  
   
   
        public static JsonSerializeProxy<T> Default  
        {  
            get 
            {  
                return _default;  
            }  
        }  
   
   
        private JsonSerializeProxy()  
        {  
            _serializer = new DataContractJsonSerializer(typeof(T));  
        }  
   
   
        public void Serialize(Stream stream, T obj)  
        {  
            _serializer.WriteObject(stream, obj);  
        }  
   
   
        /// <summary>  
        /// 将JSON字符串反序列化为对象  
        /// </summary>  
        /// <param name="jsonStr">json字符串</param>  
        /// <returns></returns>  
        public T DeSerialize(string jsonStr)  
        {  
            MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonStr));  
            T obj = (T)_serializer.ReadObject(ms);  
            return obj;  
        }  
   
   
    }