添加System.runtime.serialization.dll引用

    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;                }                            }