C# Json处理日期和Table

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Runtime.Serialization.Json;
using System.IO;
using System.Text;
using System.Text.RegularExpressions;
/// <summary>
/// JSON序列化和反序列化辅助类
/// </summary>
public class JsonHelper
{
     /// <summary>
    /// JSON序列化
    /// </summary>
     public static string JsonSerializer<T>(T t)
     {
         DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
         MemoryStream ms = new MemoryStream();
        ser.WriteObject(ms, t);
         string jsonString = Encoding.UTF8.GetString(ms.ToArray());
         ms.Close();
         //替换Json的Date字符串
         string p = @"///Date/((/d+)/+/d+/)///"; /*////Date/((([/+/-]/d+)|(/d+))[/+/-]/d+/)////*/
         MatchEvaluator matchEvaluator = new MatchEvaluator(ConvertJsonDateToDateString);
          Regex reg = new Regex(p);
         jsonString = reg.Replace(jsonString, matchEvaluator);
         return jsonString;
     }
     /// <summary>
     /// JSON反序列化
     /// </summary>
     public static T JsonDeserialize<T>(string jsonString)
     {
         //将"yyyy-MM-dd HH:mm:ss"格式的字符串转为"//Date(1294499956278+0800)//"格式
         string p = @"/d{4}-/d{2}-/d{2}/s/d{2}:/d{2}:/d{2}";
        MatchEvaluator matchEvaluator = new MatchEvaluator(ConvertDateStringToJsonDate);
        Regex reg = new Regex(p);
         jsonString = reg.Replace(jsonString, matchEvaluator);
         DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
        MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonString));
         T obj = (T)ser.ReadObject(ms);
         return obj;
     }  

     /// <summary>
     /// 将Json序列化的时间由/Date(1294499956278+0800)转为字符串
     /// </summary>
     private static string ConvertJsonDateToDateString(Match m)
     {
         string result = string.Empty;
         DateTime dt = new DateTime(,,);
         dt = dt.AddMilliseconds(long.Parse(m.Groups[].Value));
         dt = dt.ToLocalTime();
         result = dt.ToString("yyyy-MM-dd HH:mm:ss");
        return result;
     }
     /// <summary>
     /// 将时间字符串转为Json时间
     /// </summary>
     private static string ConvertDateStringToJsonDate(Match m)
     {
         string result = string.Empty;
         DateTime dt = DateTime.Parse(m.Groups[].Value);
         dt = dt.ToUniversalTime();
         TimeSpan ts = dt - DateTime.Parse("1970-01-01");
         result = string.Format("///Date({0}+0800)///",ts.TotalMilliseconds);
        return result;
    }
 }

create table Users
(
 UserId int identity(,) primary key,
 UserName varchar()
)

insert into Users values('Bradley')
insert into Users values('Dan')

 public class JsonHelper
    {
        #region  序列化和反序列化
        // 序列化
        public static  string JsonSerializer<T>(T t)
        {
            // 使用 DataContractJsonSerializer 将 T 对象序列化为内存流。
            DataContractJsonSerializer jsonSerializer = new DataContractJsonSerializer(typeof (T));
            MemoryStream ms = new MemoryStream();
            // 使用 WriteObject 方法将 JSON 数据写入到流中。
            jsonSerializer.WriteObject(ms, t);
            // 流转字符串
            string jsonString = Encoding.UTF8.GetString(ms.ToArray());
            ms.Close();
            //替换Json的Date字符串
            string p = @"\\/Date\((\d+)\+\d+\)\\/";
            MatchEvaluator matchEvaluator = new MatchEvaluator(ConvertJsonDateToDateString);
            Regex reg = new Regex(p);
            jsonString = reg.Replace(jsonString, matchEvaluator);
            return jsonString;
        }
        public static T JsonDeserialize<T>(string  jsonString)
        {
            //将"yyyy-MM-dd HH:mm:ss"格式的字符串转为"\/Date(1294499956278+0800)\/"格式
            string p = @"\d{4}-\d{2}-\d{2}\s\d{2}:\d{2}:\d{2}";
            MatchEvaluator matchEvaluator = new MatchEvaluator(ConvertDateStringToJsonDate);
            Regex reg = new Regex(p);
            jsonString = reg.Replace(jsonString, matchEvaluator);
            DataContractJsonSerializer jsonSerializer=new DataContractJsonSerializer(typeof(T));
            // 字符串转流
            MemoryStream ms=new MemoryStream(Encoding.UTF8.GetBytes(jsonString));
            // 通过使用 DataContractJsonSerializer 的 ReadObject 方法，将 JSON 编码数据反序列化为T
            T obj = (T) jsonSerializer.ReadObject(ms);
            return obj;
        }
        public static string ConvertJsonDateToDateString(Match match)
        {
            string result = string.Empty;
            DateTime dateTime=new DateTime(,,);
            dateTime = dateTime.AddMilliseconds(long.Parse(match.Groups[].Value));
            dateTime = dateTime.ToLocalTime();
            result = dateTime.ToString("yyyy-MM-dd HH:mm:ss");
            return result;
        }
        private static string ConvertDateStringToJsonDate(Match m)
        {
            string result = string.Empty;
            DateTime dt = DateTime.Parse(m.Groups[].Value);
            dt = dt.ToUniversalTime();
            TimeSpan ts = dt - DateTime.Parse("1970-01-01");
            result = string.Format("\\/Date({0}+0800)\\/",ts.TotalMilliseconds);
            return result;
        }
        #endregion

        // 对象转换为Json
        public static  string  ObjectToJson(object obj)
        {
            JavaScriptSerializer js=new JavaScriptSerializer();
            try
            {
                return js.Serialize(obj);
            }
            catch (Exception exception)
            {

                throw new Exception(exception.Message);
            }
        }
        // 数据表转化为集合
        public static List<Dictionary<string,object>> DataTableToList(DataTable dt)
        {
            List<Dictionary<string ,object>> list=new List<Dictionary<string, object>>();
            foreach (DataRow dataRow in dt.Rows)
            {
                Dictionary<string,object> dic=new Dictionary<string, object>();
                foreach (DataColumn dc in dt.Columns)
                {
                    dic.Add(dc.ColumnName,dataRow[dc.ColumnName]);
                }
                list.Add(dic);
            }
            return list;
        }
        // 表转换为Json
        public static string DataTableToJson(DataTable dt)
        {
            return ObjectToJson(DataTableToList(dt));
        }
    }
 来自：http://blog.csdn.net/cncdns/article/details/6164389

http://blog.csdn.net/bradleydan/article/details/7927862