DoNet2.0 需要借助于Newtonsoft.Json.dll

using System;
using System.IO;
using System.Text;
using Newtonsoft.Json;

namespace OfflineAcceptControl.UCTools
{
    public class JsonTools
    {
        // 从一个对象信息生成Json串
        public static string ObjectToJson(object obj)
        {
           return JavaScriptConvert.SerializeObject(obj);
        }
        // 从一个Json串生成对象信息
        public static object JsonToObject(string jsonString, object obj)
        {
           return JavaScriptConvert.DeserializeObject(jsonString, obj.GetType());
        }
    }
}

Donet3.5自带了DLL处理json串

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Json;

namespace CrjIIOfflineAccept.CrjIITools
{
    public class JsonTools
    {
        // 从一个对象信息生成Json串
        public static string ObjectToJson(object obj)
        {
           DataContractJsonSerializer serializer = new DataContractJsonSerializer(obj.GetType());
           MemoryStream stream = new MemoryStream();
           serializer.WriteObject(stream, obj);
           byte[] dataBytes = new byte[stream.Length];
           stream.Position = 0;
           stream.Read(dataBytes, 0, (int)stream.Length);
           return Encoding.UTF8.GetString(dataBytes);
        }
        // 从一个Json串生成对象信息
        public static object JsonToObject(string jsonString, object obj)
        {
           DataContractJsonSerializer serializer = new DataContractJsonSerializer(obj.GetType());
           MemoryStream mStream = new MemoryStream(Encoding.UTF8.GetBytes(jsonString));
           return serializer.ReadObject(mStream);
        }
    }
}