DataContractJsonSerializer serializer = new DataContractJsonSerializer(item.GetType());

            using (MemoryStream ms = new MemoryStream())
            {

                serializer.WriteObject(ms, item);

                StringBuilder sb = new StringBuilder();

                sb.Append(Encoding.UTF8.GetString(ms.ToArray()));

                return sb.ToString();

            }

        }

        /// <summary>
        /// Json反序列化,用于接收客戶端Json后生成對應的對象
        /// </summary>
        public static T FromJsonTo<T>(this string jsonString)
        {

            DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));

            MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonString));

            T jsonObject = (T)ser.ReadObject(ms);

            ms.Close();

            return jsonObject;

        }

                        alert(result.make);
                        alert(result.model);
                        alert(result.year);
                        alert(result.color);
                    }

                });
            });

            obj.make = "Make is Value";
            obj.model = "Model is Value";
            obj.year = 999;
            obj.color = "Color is Value";

            context.Response.Write(obj.ToJsJson());
        }
 public bool IsReusable
        {
            get
            {
                return false;
            }
        }
}

//返回值為 {"color":"Color is Value","make":"Make is Value","model":"Model is Value","year":999}

                var m_obj = { make: "Dodge", model: "Coronet R/T", year: 1968, color: "yellow" };
                var jsonStr = JSON.stringify(m_obj); //用Json2.js生成Json字符串

                $.ajax({
                    url: "postJsonHandler.ashx",
                    type: 'POST',
                    data: { postjson: jsonStr },
                    dataType: 'json',
                    timeout: 1000,
                    error: function(XMLHttpRequest, textStatus, errorThrown) { alert(textStatus) },
                    success: function(result) {

                        alert(result.success);
                    }

                });
});

            TestObj obj = jsonStr.FromJsonTo<TestObj>();

            if (string.IsNullOrEmpty(obj.make) || string.IsNullOrEmpty(obj.model) || string.IsNullOrEmpty(obj.color)

|| obj.year < 0)
            {
                context.Response.Write("{success:false}");
            }
            else
            {
                context.Response.Write("{success:true}");
            }

public bool IsReusable
        {
            get
            {
                return false;
            }
        }
}