.NET下 JSON 的一些常用操作

.NET下 JSON 的一些常用操作

 

1.JSON的序列化和反序列化

Newtonsoft.Json dll 下载地址http://json.codeplex.com/ 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Newtonsoft.Json;
 
namespace PlayJSON
{
    class Program
    {
        static void Main(string[] args)
        {
            List<StuInfo> list = new List<StuInfo>() { new StuInfo{StuName="张三",StuSex="男",StuAge=11},
                                                       new StuInfo{StuName="李四",StuSex="男",StuAge=32},
                                                       new StuInfo{StuName="王翠花",StuSex="女",StuAge=64}
                                                      };
            string jsonStr = JavaScriptConvert.SerializeObject(list);  //将对象转换成json存储
            Console.WriteLine("JSON字符串"+jsonStr);
            Console.ReadLine();
 
            List<StuInfo> newList = new List<StuInfo>();
 
           newList = (List<StuInfo>)JavaScriptConvert.DeserializeObject(jsonStr,typeof(List<StuInfo>));   //反序列化
 
            //StuInfo s = new StuInfo() { StuName = "阿龙", StuSex = "男", StuAge = 33 };
 
            //string sigleJSON = JavaScriptConvert.SerializeObject(s);
 
           //StuInfo newS = (StuInfo)JavaScriptConvert.DeserializeObject(sigleJSON);
           //Console.WriteLine("姓名:" + newS.StuName + "---性别:" + newS.StuSex + "--年龄:" + newS.StuAge + "\n\n");
 
 
           foreach (StuInfo item in newList)
           {
               Console.WriteLine("姓名:" + item.StuName + "---性别:" + item.StuSex + "--年龄:" + item.StuAge + "\n\n");
           }
            Console.ReadLine();
        }
    }
    public class StuInfo
    {
        public string StuName { set; get; }
        public string StuSex { set; get; }
        public int StuAge { set; get; }
    }
}
 

  2.在web中

 
/// <summary>
    /// Handler1 的摘要说明
    /// </summary>
    public class Handler1 : IHttpHandler
    {
 
        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "application/json";
 
            List<StuInfo> list = new List<StuInfo>() { new StuInfo{StuName="张三",StuSex="男",StuAge=11},
                                                       new StuInfo{StuName="李四",StuSex="男",StuAge=32},
                                                       new StuInfo{StuName="王翠花",StuSex="女",StuAge=64}
                                                      };
            string jsonStr = JavaScriptConvert.SerializeObject(list);
 
            context.Response.Write(jsonStr);
 
            context.Response.End();
        }
 
        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }
    public class StuInfo
    {
        public string StuName { set; get; }
        public string StuSex { set; get; }
        public int StuAge { set; get; }
    }

  前台页面上的调用:这里采用jquery 的ajax请求

复制代码
<head runat="server">
    <title>JSON</title>
    <script src="Scripts/jquery-1.4.1.min.js" type="text/javascript"></script>
    <script type="text/javascript">
        $(function () {
            $("#btnOK").click(function () {
                $.ajax({
                    type: "JSON",
                    url: "Handler1.ashx",
                    data: null,
                    success: function (msg) {
                        var con="";
                        for (var i = 0; i < msg.length; i++) {
                            con += "姓名:" + msg[i].StuName + "--性别:" + msg[i].StuSex + "--" + "--年龄:" + msg[i].StuAge+"<br/>";
                        }

                        $("#divContent").html("长度:" + msg.length + "--具体内容:<br/>" + con);
                    }
                });
            });
        });
    </script>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <input type="button" id="btnOK" value="点我获得JSON数据" />
    <div id="divContent"></div>
    </div>
    </form>
</body>
复制代码

现在经常会用到json,因此经常会需要对其进行序列化和反序列化。,.NET Framewok 3.5也提供了JSON对象序列化和反序列化的类,这就是System.Runtime.Serialization.Json 命名空间下的 DataContractJsonSerializer 类。利用这个类,可以实现JSON对象的序列化和反序列化。

现在我提供一个类JSON对象序列化和反序列化的类供参考用:

/// <summary>
    /// JSON帮助类。用于将对象转换为Json格式的字符串,或者将Json的字符串转化为对象。
    /// </summary>
    public static class JsonHelper
    {
        /// <summary>
        /// 将对象转化为Json字符串
        /// </summary>
        /// <typeparam name="T">源类型</typeparam>
        /// <param name="obj">源类型实例</param>
        /// <returns>Json字符串</returns>
        public static string GetJsonFromObj<T>(T obj)
        {
            DataContractJsonSerializer jsonSerializer = new DataContractJsonSerializer(obj.GetType());
            using (MemoryStream ms = new MemoryStream())
            {
                jsonSerializer.WriteObject(ms, obj);
                return Encoding.UTF8.GetString(ms.ToArray());
            }
        }
 
        /// <summary>
        /// 将Json字符串转化为对象
        /// </summary>
        /// <typeparam name="T">目标类型</typeparam>
        /// <param name="strJson">Json字符串</param>
        /// <returns>目标类型的一个实例</returns>
        public static T GetObjFromJson<T>(string strJson)
        {
            T obj = Activator.CreateInstance<T>();
            using (MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(strJson)))
            {
                DataContractJsonSerializer jsonSerializer = new DataContractJsonSerializer(obj.GetType());
                return (T)jsonSerializer.ReadObject(ms);
            }
        }
 
        /// <summary>
        /// 将DataTable转换为JSON字符串
        /// </summary>
        /// <param name="dt">数据表</param>
        /// <returns>JSON字符串</returns>
        public static string GetJsonFromDataTable(DataTable dt)
        {
            StringBuilder JsonString = new StringBuilder();
            if (dt != null && dt.Rows.Count > 0)
            {
                JsonString.Append("{ ");
                JsonString.Append("\"TableInfo\":[ ");
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    JsonString.Append("{ ");
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        if (j < dt.Columns.Count - 1)
                        {
                            JsonString.Append("\"" + dt.Columns[j].ColumnName.ToString() + "\":" + "\"" + dt.Rows[i][j].ToString() + "\",");
                        }
                        else if (j == dt.Columns.Count - 1)
                        {
                            JsonString.Append("\"" + dt.Columns[j].ColumnName.ToString() + "\":" + "\"" + dt.Rows[i][j].ToString() + "\"");
                        }
                    }
                    if (i == dt.Rows.Count - 1)
                    {
                        JsonString.Append("} ");
                    }
                    else
                    {
                        JsonString.Append("}, ");
                    }
                }
                JsonString.Append("]}");
                return JsonString.ToString();
            }
            else
            {
                return null;
            }
        }
 
        /// <summary>
        /// 将对象转化为Json字符串
        /// </summary>
        /// <param name="obj">源对象</param>
        /// <returns>json数据</returns>
        public static string ObjToJson(this object obj)
        {
            JavaScriptSerializer serialize = new JavaScriptSerializer();
            return serialize.Serialize(obj);
        }
 
        /// <summary>
        /// 将Json字符串转化为对象
        /// </summary>
        /// <param name="strJson">Json字符串</param>
        /// <returns>目标对象</returns>
        public static T JsonToObj<T>(string strJson)
        {
            JavaScriptSerializer serialize = new JavaScriptSerializer();
            return serialize.Deserialize<T>(strJson);
        }
 
        /// <summary>
        /// 将对象转化为Json字符串(控制深度 )
        /// </summary>
        /// <param name="obj">源对象</param>
        /// <param name="recursionDepth">深度</param>
        /// <returns>json数据</returns>
        public static string ObjToJson(this object obj, int recursionDepth)
        {
            JavaScriptSerializer serialize = new JavaScriptSerializer();
            serialize.RecursionLimit = recursionDepth;
            return serialize.Serialize(obj);
        }
 
        /// <summary>
        /// 将Json字符串转化为对象(控制深度 )
        /// </summary>
        /// <param name="strJson">Json字符串</param>
        /// <param name="recursionDepth">深度</param>
        /// <returns>目标对象</returns>
        public static T JsonToObj<T>(string strJson, int recursionDepth)
        {
            JavaScriptSerializer serialize = new JavaScriptSerializer();
            serialize.RecursionLimit = recursionDepth;
            return serialize.Deserialize<T>(strJson);
        }
 
        /// <summary>
        /// 将DataTable转换为JSON字符串
        /// </summary>
        /// <param name="dt">DataTable</param>
        /// <returns>json数据</returns>
        public static string DataTableToJson(DataTable dt)
        {
            Dictionary<string, object> dic = new Dictionary<string, object>();
 
            int index = 0;
            foreach (DataRow dr in dt.Rows)
            {
                Dictionary<string, object> result = new Dictionary<string, object>();
 
                foreach (DataColumn dc in dt.Columns)
                {
                    result.Add(dc.ColumnName, dr[dc].ToString());
                }
                dic.Add(index.ToString(), result);
                index++;
            }
            return ObjToJson(dic);
        }
    }

  使用如下:

按 Ctrl+C 复制代码
按 Ctrl+C 复制代码

 

posted on 2013-08-13 17:14  【波少】  阅读(196)  评论(0编辑  收藏  举报

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