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  • Json的序列化与反序列化

    方法一:引入System.Web.Script.Serialization命名空间使用 JavaScriptSerializer类实现简单的序列化

     //第一种序列化反序列化方式
                personel person = new personel() { Age = 13, Name = "我是序列化" };
                JavaScriptSerializer JsStringJson = new JavaScriptSerializer();
                //执行序列化
                string r9 = JsStringJson.Serialize(person);
                //执行反序列化
                personel Fperson = JsStringJson.Deserialize<personel>(r9);

    方法二:引入 System.Runtime.Serialization.Json命名空间使用 DataContractJsonSerializer类实现序列化

    //第二种序列化反序列化方式
                IList<personel> ListPerson = new List<personel>() { new personel() { Age = 16, Name = "郑序列" }, new personel() { Name = "反序列", Age = 48 } };
                DataContractJsonSerializer jsonString = new DataContractJsonSerializer(ListPerson.GetType());
                //序列化
                string toJson = "";
                using (MemoryStream strem = new MemoryStream())
                {
                    jsonString.WriteObject(strem, ListPerson);
                    toJson = Encoding.UTF8.GetString(strem.ToArray());
                }
                //反序列化
                using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(toJson)))
                {
                    DataContractJsonSerializer dcjs = new DataContractJsonSerializer(typeof(List<personel>));
                    List<personel> peoeo = (List<personel>)dcjs.ReadObject(ms);
                }

    可以使用IgnoreDataMember:指定该成员不是数据协定的一部分且没有进行序列化,DataMember:定义序列化属性参数,使用DataMember属性标记字段必须使用DataContract标记类 否则DataMember标记不起作用。

    方法三:Json.Net

    using (var stringReader = new StringReader(data))
    using (var jsonTextReader = new JsonTextReader(stringReader))
    {
        var serializer = new JsonSerializer();
        var employees = serializer.Deserialize<Employee[]>(jsonTextReader);
    }

    -------------------------------------------------------------------------------------------------------------------------------------

         JSON(JavaScript Object Notation,JavaScript对象表示法)是一种轻量级的数据交换格式。

    JSON是“名值对”的集合。结构由大括号'{}',中括号'[]',逗号',',冒号':',双引号'“”'组成,包含的数据类型有Object,Number,Boolean,String,Array, NULL等。

    JSON具有以下的形式:

    对象(Object)是一个无序的“名值对”集合,一个对象以”{”开始,”}”结束。每个“名”后跟着一个”:”,多个“名值对”由逗号分隔。如:

    var user={"name":"张三","gender":"","birthday":"1980-8-8"}

    数组(Array)是值的有序集合,一个数组以“[”开始,以“]”结束,值之间使用“,”分隔。如:

    var userlist=[{"user":{"name":"张三","gender":"","birthday":"1980-8-8"}},{"user":{"name":"李四","gender":"","birthday":"1985-5-8"}}];

    字符串(String)是由双引号包围的任意数量的Unicode字符的集合,使用反斜线转义。

    二、对JSON数据进行序列化和反序列化

    可以使用DataContractJsonSerializer类将类型实例序列化为JSON字符串,并将JSON字符串反序列化为类型实例。DataContractJsonSerializer在System.Runtime.Serialization.Json命名空间下,.NET Framework 3.5包含在System.ServiceModel.Web.dll中,需要添加对其的引用;.NET Framework 4在System.Runtime.Serialization中。

    利用DataContractJsonSerializer序列化和反序列化的代码:

    1: using System;
       2: using System.Collections.Generic;
       3: using System.Linq;
       4: using System.Web;
       5: using System.Runtime.Serialization.Json;
       6: using System.IO;
       7: using System.Text;
       8:  
       9: /// <summary>
      10: /// JSON序列化和反序列化辅助类
      11: /// </summary>
      12: public class JsonHelper
      13: {
      14:     /// <summary>
      15:     /// JSON序列化
      16:     /// </summary>
      17:     public static string JsonSerializer<T>(T t)
      18:     {
      19:         DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
      20:         MemoryStream ms = new MemoryStream();
      21:         ser.WriteObject(ms, t);
      22:         string jsonString = Encoding.UTF8.GetString(ms.ToArray());
      23:         ms.Close();
      24:         return jsonString;
      25:     }
      26:  
      27:     /// <summary>
      28:     /// JSON反序列化
      29:     /// </summary>
      30:     public static T JsonDeserialize<T>(string jsonString)
      31:     {
      32:         DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
      33:         MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonString));
      34:         T obj = (T)ser.ReadObject(ms);
      35:         return obj;
      36:     }
      37: }

    序列化Demo:

    简单对象Person:

       1: public class Person
       2: {
       3:     public string Name { get; set; }
       4:     public int Age { get; set; }
       5: }

    序列化为JSON字符串:

       1: protected void Page_Load(object sender, EventArgs e)
       2: {
       3:     Person p = new Person();
       4:     p.Name = "张三";
       5:     p.Age = 28;
       6:  
       7:     string jsonString = JsonHelper.JsonSerializer<Person>(p);
       8:     Response.Write(jsonString);
       9: }

    输出结果:

    {"Age":28,"Name":"张三"} 

    反序列化Demo:

       1: protected void Page_Load(object sender, EventArgs e)
       2: {
       3:     string jsonString = "{"Age":28,"Name":"张三"}";
       4:     Person p = JsonHelper.JsonDeserialize<Person>(jsonString);
       5: }

    运行结果:

    image

    ASP.NET中的JSON序列化和反序列化还可以使用JavaScriptSerializer,在System.Web.Script.Serializatioin命名空间下,需引用System.Web.Extensions.dll.也可以使用JSON.NET.

    三、JSON序列化和反序列化日期时间的处理

    JSON格式不直接支持日期和时间。DateTime值值显示为“/Date(700000+0500)/”形式的JSON字符串,其中第一个数字(在提供的示例中为 700000)是 GMT 时区中自 1970 年 1 月 1 日午夜以来按正常时间(非夏令时)经过的毫秒数。该数字可以是负数,以表示之前的时间。示例中包括“+0500”的部分可选,它指示该时间属于Local类型,即它在反序列化时应转换为本地时区。如果没有该部分,则会将时间反序列化为Utc。

    修改Person类,添加LastLoginTime:

       1: public class Person
       2: {
       3:     public string Name { get; set; }
       4:     public int Age { get; set; }
       5:     public DateTime LastLoginTime { get; set; }
       6: }
       1: Person p = new Person();
       2: p.Name = "张三";
       3: p.Age = 28;
       4: p.LastLoginTime = DateTime.Now;
       5:  
       6: string jsonString = JsonHelper.JsonSerializer<Person>(p);

    序列化结果:

    {"Age":28,"LastLoginTime":"/Date(1294499956278+0800)/","Name":"张三"}
     

    1 、在后台使用正则表达式对其替换处理。修改JsonHelper:

     1: using System;
       2: using System.Collections.Generic;
       3: using System.Linq;
       4: using System.Web;
       5: using System.Runtime.Serialization.Json;
       6: using System.IO;
       7: using System.Text;
       8: using System.Text.RegularExpressions;
       9:  
      10: /// <summary>
      11: /// JSON序列化和反序列化辅助类
      12: /// </summary>
      13: public class JsonHelper
      14: {
      15:     /// <summary>
      16:     /// JSON序列化
      17:     /// </summary>
      18:     public static string JsonSerializer<T>(T t)
      19:     {
      20:         DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
      21:         MemoryStream ms = new MemoryStream();
      22:         ser.WriteObject(ms, t);
      23:         string jsonString = Encoding.UTF8.GetString(ms.ToArray());
      24:         ms.Close();
      25:         //替换Json的Date字符串
      26:         string p = @"\/Date((d+)+d+)\/";
      27:         MatchEvaluator matchEvaluator = new MatchEvaluator(ConvertJsonDateToDateString);
      28:          Regex reg = new Regex(p);
      29:         jsonString = reg.Replace(jsonString, matchEvaluator);
      30:         return jsonString;
      31:     }
      32:  
      33:     /// <summary>
      34:     /// JSON反序列化
      35:     /// </summary>
      36:     public static T JsonDeserialize<T>(string jsonString)
      37:     {
      38:         //将"yyyy-MM-dd HH:mm:ss"格式的字符串转为"/Date(1294499956278+0800)/"格式
      39:         string p = @"d{4}-d{2}-d{2}sd{2}:d{2}:d{2}";
      40:         MatchEvaluator matchEvaluator = new MatchEvaluator(ConvertDateStringToJsonDate);
      41:         Regex reg = new Regex(p);
      42:         jsonString = reg.Replace(jsonString, matchEvaluator);
      43:         DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
      44:         MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(jsonString));
      45:         T obj = (T)ser.ReadObject(ms);
      46:         return obj;
      47:     }
      48:  
      49:     /// <summary>
      50:     /// 将Json序列化的时间由/Date(1294499956278+0800)转为字符串
      51:     /// </summary>
      52:     private static string ConvertJsonDateToDateString(Match m)
      53:     {
      54:         string result = string.Empty;
      55:         DateTime dt = new DateTime(1970,1,1);
      56:         dt = dt.AddMilliseconds(long.Parse(m.Groups[1].Value));
      57:         dt = dt.ToLocalTime();
      58:         result = dt.ToString("yyyy-MM-dd HH:mm:ss");
      59:         return result;
      60:     }
      61:  
      62:     /// <summary>
      63:     /// 将时间字符串转为Json时间
      64:     /// </summary>
      65:     private static string ConvertDateStringToJsonDate(Match m)
      66:     {
      67:         string result = string.Empty;
      68:         DateTime dt = DateTime.Parse(m.Groups[0].Value);
      69:         dt = dt.ToUniversalTime();
      70:         TimeSpan ts = dt - DateTime.Parse("1970-01-01");
      71:         result = string.Format("\/Date({0}+0800)\/",ts.TotalMilliseconds);
      72:         return result;
      73:     }
      74: }

    序列化Demo:

       1: Person p = new Person();
       2: p.Name = "张三";
       3: p.Age = 28;
       4: p.LastLoginTime = DateTime.Now;
       5:  
       6: string jsonString = JsonHelper.JsonSerializer<Person>(p);

    运行结果:

    {"Age":28,"LastLoginTime":"2011-01-09 01:00:56","Name":"张三"}

    反序列化Demo:

    string json = "{"Age":28,"LastLoginTime":"2011-01-09 00:30:00","Name":"张三"}";
    p=JsonHelper.JsonDeserialize<Person>(json);

    运行结果:

    image

    在后台替换字符串适用范围比较窄,如果考虑到全球化的有多种语言还会更麻烦。

    2、利用JavaScript处理

       1: function ChangeDateFormat(jsondate) {
       2:     jsondate = jsondate.replace("/Date(", "").replace(")/", "");
       3:     if (jsondate.indexOf("+") > 0) {
       4:         jsondate = jsondate.substring(0, jsondate.indexOf("+"));
       5:     }
       6:     else if (jsondate.indexOf("-") > 0) {
       7:         jsondate = jsondate.substring(0, jsondate.indexOf("-"));
       8:     }
       9:  
      10:     var date = new Date(parseInt(jsondate, 10));
      11:     var month = date.getMonth() + 1 < 10 ? "0" + (date.getMonth() + 1) : date.getMonth() + 1;
      12:     var currentDate = date.getDate() < 10 ? "0" + date.getDate() : date.getDate();
      13:     return date.getFullYear() + "-" + month + "-" + currentDate;
      14: }

    简单Demo :

    ChangeDateFormat("/Date(1294499956278+0800)/");

    结果:

    2011-1-8

    四、JSON序列化和反序列化集合、字典、数组的处理

    在JSON数据中,所有的集合、字典和数组都表示为数组。

    List<T>序列化:

       1: List<Person> list = new List<Person>()
       2: {
       3:     new Person(){ Name="张三", Age=28},
       4:     new Person(){ Name="李四", Age=25}
       5: };
       6:  
       7: string jsonString = JsonHelper.JsonSerializer<List<Person>>(list);

    序列化结果:

    "[{"Age":28,"Name":"张三"},{"Age":25,"Name":"李四"}]"

    字典不能直接用于JSON,Dictionary字典转化为JSON并不是跟原来的字典格式一致,而是形式以Dictionary的Key作为名称”Key“的值,以Dictionary的Value作为名称为”Value“的值 。如:

       1: Dictionary<string, string> dic = new Dictionary<string, string>();
       2: dic.Add("Name", "张三");
       3: dic.Add("Age", "28");
       4:  
       5: string jsonString = JsonHelper.JsonSerializer < Dictionary<string, string>>(dic);

    序列化结果:

       1: "[{"Key":"Name","Value":"张三"},{"Key":"Age","Value":"28"}]"

     转载自:http://www.cnblogs.com/zhaozhan/archive/2011/01/09/1931340.html

    【版权所有@ithuo】 【博客地址 http://www.cnblogs.com/ithuo】 可以转载,但请注明出处并保持博客超链接,有不正确的地方请不吝赐教,谢谢大家的帮助与支持!
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  • 原文地址:https://www.cnblogs.com/ithuo/p/4755080.html
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