jsonDLL 使用方法

我们知道在.NET中我们有多种对象序列化的方式,如XML方式序列化、Binary序列化,其中XML序列化是一种比较通用的在各语言之间传递数据的方式。除了这两种序列化方式之外,在.NET中还可以使用JSON序列化。 JSON(JavaScript Object Notation)是一种轻量级轻量级的数据交换格式,并且它独立于编程语言,与XML序列化相比,JSON序列化后产生的数据一般要比XML序列化后数据体积小,所以在Facebook等知名网站中都采用了JSON作为数据交换方式。在.NET中有三种常用的JSON序列化的类,分别是System.Web.Script.Serialization.JavaScriptSerializer类、System.Runtime.Serialization.Json.DataContractJsonSerializer类和Newtonsoft.Json.JsonConvert类。 为了便于下面的演示,下面提供一个类的代码:

 
  1. [DataContract] 
  2. publicclass User 
  3. { 
  4.     /// <summary> 
  5.     /// 编号 
  6.     /// </summary> 
  7.     [DataMember] 
  8.     publicint UserId { get; set; } 
  9.     /// <summary> 
  10.     /// 用户名 
  11.     /// </summary> 
  12.     [DataMember] 
  13.     publicstring UserName { get; set; } 
  14.     /// <summary> 
  15.     /// 创建时间 
  16.     /// </summary> 
  17.     [DataMember] 
  18.     [JsonConverter(typeof(IsoDateTimeConverter))] 
  19.     public DateTime CreateDate { get; set; } 
  20.     /// <summary> 
  21.     /// 生日 
  22.     /// </summary> 
  23.     [DataMember] 
  24.     [JsonConverter(typeof(JavaScriptDateTimeConverter))] 
  25.     public DateTime Birthday { get; set; } 
  26.     /// <summary> 
  27.     /// 相关URL 
  28.     /// </summary> 
  29.     [DataMember] 
  30.     public List<string> Urls { get; set; } 
  31.     /// <summary> 
  32.     /// 薪水 
  33.     /// </summary> 
  34.     //[ScriptIgnore]//使用JavaScriptSerializer序列化时不序列化此字段 
  35.     //[IgnoreDataMember]//使用DataContractJsonSerializer序列化时不序列化此字段 
  36.     //[JsonIgnore]//使用JsonConvert序列化时不序列化此字段 
  37.     publicint Salary { get; set; } 
  38.     /// <summary> 
  39.     /// 权利级别 
  40.     /// </summary> 
  41.     [DataMember] 
  42.     public Priority Priority { get; set; } 
  43.  
  44.     public User() 
  45.     { 
  46.         Urls = new List<string>(); 
  47.     } 
  48. } 
  49. /// <summary> 
  50. /// 权利级别 
  51. /// </summary> 
  52. publicenum Priority:byte 
  53. { 
  54.     Lowest=0x1, 
  55.     BelowNormal=0x2, 
  56.     Normal=0x4, 
  57.     AboveNormal=0x8, 
  58.     Highest=0x16 
  59. } 

 

使用System.Web.Script.Serialization.JavaScriptSerializer类System.Web.Script.Serialization.JavaScriptSerializer类是.NET类库中自带的一种JSON序列化实现,在.NET Framework3.5及以后版本中可以使用这个类,这个类位于System.Web.Extensions.dll中,使用这个类是必须添加对这个dll的引用。 下面的代码是使用JavaScriptSerializer进行序列化和反序列化的例子:

 
  1. publicstaticvoid JavaScriptSerializerDemo() 
  2. { 
  3.     User user = new User { UserId = 1, UserName = "李刚", CreateDate = DateTime.Now.AddYears(-30),Birthday=DateTime.Now.AddYears(-50), Priority = Priority.Highest, Salary = 500000 }; 
  4.     //JavaScriptSerializer类在System.Web.Extensions.dll中,注意添加这个引用 
  5.     JavaScriptSerializer serializer = new JavaScriptSerializer(); 
  6.     //JSON序列化 
  7.     string result=serializer.Serialize(user); 
  8.     Console.WriteLine("使用JavaScriptSerializer序列化后的结果:{0},长度:{1}", result, result.Length); 
  9.     //JSON反序列化 
  10.     user = serializer.Deserialize<User>(result); 
  11.     Console.WriteLine("使用JavaScriptSerializer反序列化后的结果:UserId:{0},UserName:{1},CreateDate:{2},Priority:{3}", user.UserId, user.UserName, user.CreateDate, user.Priority); 
  12.  
  13. } 

说明:如果不想序列化某个字段,可以在字段前面加[JsonIgnore]标记。

 

使用System.Runtime.Serialization.Json.DataContractJsonSerializer类 System.Runtime.Serialization.Json.DataContractJsonSerializer类位于System.ServiceModel.Web.dll中,使用这个类时除了需要添加对System.ServiceModel.Web.dll的引用之外,还需要添加System.Runtime.Serialization.dll的引用,注意这个类也是在.NET Framework3.5及以后版本中可以使用。 下面是使用DataContractJsonSerializer类的例子:

 
  1. publicstaticvoid DataContractJsonSerializerDemo() 
  2. { 
  3.     User user = new User { UserId = 1, UserName = "李刚", CreateDate = DateTime.Now.AddYears(-30), Birthday = DateTime.Now.AddYears(-50), Priority = Priority.AboveNormal, Salary = 50000 }; 
  4.     string result = string.Empty; 
  5.     //DataContractJsonSerializer类在System.ServiceModel.Web.dll中,注意添加这个引用 
  6.     DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(User)); 
  7.      
  8.     using (MemoryStream stream = new MemoryStream()) 
  9.     { 
  10.         //JSON序列化 
  11.         serializer.WriteObject(stream, user); 
  12.         result = Encoding.UTF8.GetString(stream.ToArray()); 
  13.         Console.WriteLine("使用DataContractJsonSerializer序列化后的结果:{0},长度:{1}", result, result.Length); 
  14.     } 
  15.  
  16.     //JSON反序列化 
  17.     byte[] buffer = Encoding.UTF8.GetBytes(result); 
  18.     using (MemoryStream stream = new MemoryStream(buffer)) 
  19.     { 
  20.         user = serializer.ReadObject(stream) as User; 
  21.         Console.WriteLine("使用DataContractJsonSerializer反序列化后的结果:UserId:{0},UserName:{1},CreateDate:{2},Priority:{3}", user.UserId, user.UserName, user.CreateDate, user.Priority); 
  22.     } 
  23. } 

注意:要使用DataContractJsonSerializer类进行序列化和反序列化,必须给类加上[DataContract]属性,对要序列化的字段加上[DataMember]属性,如果不想序列化某个字段或者属性,可以加上[IgnoreDataMember]属性。

 

使用Newtonsoft.Json.JsonConvert类 Newtonsoft.Json.JsonConvert类是非微软提供的一个JSON序列化和反序列的开源免费的类库(下载网址是:http://www.codeplex.com/json/),它提供了更灵活的序列化和反序列化控制,并且如果你的开发环境使用的是.NET Framework3.5及以后版本的话,你就可以使用Linq to JSON,这样一来面对一大段的数据不必一一解析,你可以使用Linq to JSON解析出你关心的那部分即可,非常方便。 下面是使用Newtonsoft.Json.JsonConvert类的例子:

 
  1. publicstaticvoid JsonConvertDemo() 
  2. { 
  3.     User user = new User { UserId = 1, UserName = "李刚", CreateDate = DateTime.Now.AddYears(-30), Birthday = DateTime.Now.AddYears(-50), Priority = Priority.BelowNormal, Salary = 5000 }; 
  4.     //JsonConvert类在Newtonsoft.Json.Net35.dll中,注意到http://www.codeplex.com/json/下载这个dll并添加这个引用 
  5.     //JSON序列化 
  6.     string result = JsonConvert.SerializeObject(user); 
  7.     Console.WriteLine("使用JsonConvert序列化后的结果:{0},长度:{1}", result, result.Length); 
  8.     //JSON反序列化 
  9.     user = JsonConvert.DeserializeObject<User>(result); 
  10.     Console.WriteLine("使用JsonConvert反序列化后的结果:UserId:{0},UserName:{1},CreateDate:{2},Priority:{3}", user.UserId, user.UserName, user.CreateDate, user.Priority); 
  11. } 
  12.  
  13. publicstaticvoid JsonConvertLinqDemo() 
  14. { 
  15.     User user = new User { UserId = 1, UserName = "周公", CreateDate = DateTime.Now.AddYears(-8), Birthday = DateTime.Now.AddYears(-32), Priority = Priority.Lowest, Salary = 500, Urls = new List<string> { "http://zhoufoxcn.blog.51cto.com", "http://blog.csdn.net/zhoufoxcn" } }; 
  16.     //JsonConvert类在Newtonsoft.Json.Net35.dll中,注意到http://www.codeplex.com/json/下载这个dll并添加这个引用 
  17.     //JSON序列化 
  18.     string result = JsonConvert.SerializeObject(user); 
  19.     Console.WriteLine("使用JsonConvert序列化后的结果:{0},长度:{1}", result, result.Length); 
  20.     //使用Linq to JSON 
  21.     JObject jobject = JObject.Parse(result); 
  22.     JToken token = jobject["Urls"]; 
  23.     List<string> urlList = new List<string>(); 
  24.     foreach (JToken t in token) 
  25.     { 
  26.         urlList.Add(t.ToString()); 
  27.     } 
  28.     Console.Write("使用Linq to JSON反序列化后的结果:["); 
  29.     for (int i = 0; i < urlList.Count - 1;i++ ) 
  30.     { 
  31.         Console.Write(urlList[i] + ","); 
  32.     } 
  33.     Console.WriteLine(urlList[urlList.Count - 1] + "]"); 
  34. } 

注意:如果有不需要序列化的字段,可以给该字段添加[JsonIgnore]标记。在Newtonsoft这个类库中对于日期的序列化有多种方式,可以类的DataTime成员添加上对应的标记,这样在进行序列化和反序列化时就会按照指定的方式进行,在本例中User类的CreateDate属性添加的属性是[JsonConverter(typeof(IsoDateTimeConverter))],而Birthday属性添加的属性是[JsonConverter(typeof(JavaScriptDateTimeConverter))],从序列化的结果可以看出来它们最终的表现形式并不一样。 本文中所有的示例代码如下:

 
  1. using System; 
  2. using System.Collections.Generic; 
  3. using System.Linq; 
  4. using System.Text; 
  5. using System.Web.Script.Serialization; 
  6. using System.Runtime.Serialization.Json; 
  7. using System.IO; 
  8. using System.Runtime.Serialization; 
  9. using Newtonsoft.Json; 
  10. using Newtonsoft.Json.Linq; 
  11. using Newtonsoft.Json.Converters; 
  12.  
  13. namespace JSONDemo 
  14. { 
  15. class Program 
  16. { 
  17.     staticvoid Main(string[] args) 
  18.     { 
  19.         JavaScriptSerializerDemo(); 
  20.         DataContractJsonSerializerDemo(); 
  21.         JsonConvertDemo(); 
  22.         JsonConvertLinqDemo(); 
  23.         Console.ReadLine(); 
  24.     } 
  25.  
  26.     publicstaticvoid JavaScriptSerializerDemo() 
  27.     { 
  28.         User user = new User { UserId = 1, UserName = "李刚", CreateDate = DateTime.Now.AddYears(-30),Birthday=DateTime.Now.AddYears(-50), Priority = Priority.Highest, Salary = 500000 }; 
  29.         //JavaScriptSerializer类在System.Web.Extensions.dll中,注意添加这个引用 
  30.         JavaScriptSerializer serializer = new JavaScriptSerializer(); 
  31.         //JSON序列化 
  32.         string result=serializer.Serialize(user); 
  33.         Console.WriteLine("使用JavaScriptSerializer序列化后的结果:{0},长度:{1}", result, result.Length); 
  34.         //JSON反序列化 
  35.         user = serializer.Deserialize<User>(result); 
  36.         Console.WriteLine("使用JavaScriptSerializer反序列化后的结果:UserId:{0},UserName:{1},CreateDate:{2},Priority:{3}", user.UserId, user.UserName, user.CreateDate, user.Priority); 
  37.  
  38.     } 
  39.  
  40.     publicstaticvoid DataContractJsonSerializerDemo() 
  41.     { 
  42.         User user = new User { UserId = 1, UserName = "李刚", CreateDate = DateTime.Now.AddYears(-30), Birthday = DateTime.Now.AddYears(-50), Priority = Priority.AboveNormal, Salary = 50000 }; 
  43.         string result = string.Empty; 
  44.         //DataContractJsonSerializer类在System.ServiceModel.Web.dll中,注意添加这个引用 
  45.         DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(User)); 
  46.          
  47.         using (MemoryStream stream = new MemoryStream()) 
  48.         { 
  49.             //JSON序列化 
  50.             serializer.WriteObject(stream, user); 
  51.             result = Encoding.UTF8.GetString(stream.ToArray()); 
  52.             Console.WriteLine("使用DataContractJsonSerializer序列化后的结果:{0},长度:{1}", result, result.Length); 
  53.         } 
  54.  
  55.         //JSON反序列化 
  56.         byte[] buffer = Encoding.UTF8.GetBytes(result); 
  57.         using (MemoryStream stream = new MemoryStream(buffer)) 
  58.         { 
  59.             user = serializer.ReadObject(stream) as User; 
  60.             Console.WriteLine("使用DataContractJsonSerializer反序列化后的结果:UserId:{0},UserName:{1},CreateDate:{2},Priority:{3}", user.UserId, user.UserName, user.CreateDate, user.Priority); 
  61.         } 
  62.     } 
  63.  
  64.     publicstaticvoid JsonConvertDemo() 
  65.     { 
  66.         User user = new User { UserId = 1, UserName = "李刚", CreateDate = DateTime.Now.AddYears(-30), Birthday = DateTime.Now.AddYears(-50), Priority = Priority.BelowNormal, Salary = 5000 }; 
  67.         //JsonConvert类在Newtonsoft.Json.Net35.dll中,注意到http://www.codeplex.com/json/下载这个dll并添加这个引用 
  68.         //JSON序列化 
  69.         string result = JsonConvert.SerializeObject(user); 
  70.         Console.WriteLine("使用JsonConvert序列化后的结果:{0},长度:{1}", result, result.Length); 
  71.         //JSON反序列化 
  72.         user = JsonConvert.DeserializeObject<User>(result); 
  73.         Console.WriteLine("使用JsonConvert反序列化后的结果:UserId:{0},UserName:{1},CreateDate:{2},Priority:{3}", user.UserId, user.UserName, user.CreateDate, user.Priority); 
  74.     } 
  75.  
  76.     publicstaticvoid JsonConvertLinqDemo() 
  77.     { 
  78.         User user = new User { UserId = 1, UserName = "周公", CreateDate = DateTime.Now.AddYears(-8), Birthday = DateTime.Now.AddYears(-32), Priority = Priority.Lowest, Salary = 500, Urls = new List<string> { "http://zhoufoxcn.blog.51cto.com", "http://blog.csdn.net/zhoufoxcn" } }; 
  79.         //JsonConvert类在Newtonsoft.Json.Net35.dll中,注意到http://www.codeplex.com/json/下载这个dll并添加这个引用 
  80.         //JSON序列化 
  81.         string result = JsonConvert.SerializeObject(user); 
  82.         Console.WriteLine("使用JsonConvert序列化后的结果:{0},长度:{1}", result, result.Length); 
  83.         //使用Linq to JSON 
  84.         JObject jobject = JObject.Parse(result); 
  85.         JToken token = jobject["Urls"]; 
  86.         List<string> urlList = new List<string>(); 
  87.         foreach (JToken t in token) 
  88.         { 
  89.             urlList.Add(t.ToString()); 
  90.         } 
  91.         Console.Write("使用Linq to JSON反序列化后的结果:["); 
  92.         for (int i = 0; i < urlList.Count - 1;i++ ) 
  93.         { 
  94.             Console.Write(urlList[i] + ","); 
  95.         } 
  96.         Console.WriteLine(urlList[urlList.Count - 1] + "]"); 
  97.     } 
  98. } 
  99.  
  100. [DataContract] 
  101. publicclass User 
  102. { 
  103.     /// <summary> 
  104.     /// 编号 
  105.     /// </summary> 
  106.     [DataMember] 
  107.     publicint UserId { get; set; } 
  108.     /// <summary> 
  109.     /// 用户名 
  110.     /// </summary> 
  111.     [DataMember] 
  112.     publicstring UserName { get; set; } 
  113.     /// <summary> 
  114.     /// 创建时间 
  115.     /// </summary> 
  116.     [DataMember] 
  117.     [JsonConverter(typeof(IsoDateTimeConverter))] 
  118.     public DateTime CreateDate { get; set; } 
  119.     /// <summary> 
  120.     /// 生日 
  121.     /// </summary> 
  122.     [DataMember] 
  123.     [JsonConverter(typeof(JavaScriptDateTimeConverter))] 
  124.     public DateTime Birthday { get; set; } 
  125.     /// <summary> 
  126.     /// 相关URL 
  127.     /// </summary> 
  128.     [DataMember] 
  129.     public List<string> Urls { get; set; } 
  130.     /// <summary> 
  131.     /// 薪水 
  132.     /// </summary> 
  133.     [ScriptIgnore]//使用JavaScriptSerializer序列化时不序列化此字段 
  134.     [IgnoreDataMember]//使用DataContractJsonSerializer序列化时不序列化此字段 
  135.     [JsonIgnore]//使用JsonConvert序列化时不序列化此字段 
  136.     publicint Salary { get; set; } 
  137.     /// <summary> 
  138.     /// 权利级别 
  139.     /// </summary> 
  140.     [DataMember] 
  141.     public Priority Priority { get; set; } 
  142.  
  143.     public User() 
  144.     { 
  145.         Urls = new List<string>(); 
  146.     } 
  147. } 
  148. /// <summary> 
  149. /// 权利级别 
  150. /// </summary> 
  151. publicenum Priority:byte 
  152. { 
  153.     Lowest=0x1, 
  154.     BelowNormal=0x2, 
  155.     Normal=0x4, 
  156.     AboveNormal=0x8, 
  157.     Highest=0x16 
  158. } 
  159. } 

程序的运行结果如下:

 

  1. 使用JavaScriptSerializer序列化后的结果:{"UserId":1,"UserName":"李刚","CreateDate":"//Date(353521211984)//","Birthday":"//Date(-277630788015)//","Urls":[],"Priority":22},长度:127 
  2. 使用JavaScriptSerializer反序列化后的结果:UserId:1,UserName:李刚,CreateDate:1981-3-15 16:20:11,Priority:Highest 
  3. 使用DataContractJsonSerializer序列化后的结果:{"Birthday":"//Date(-277630787953+0800)//","CreateDate":"//Date(353521212046+0800)//","Priority":8,"Urls":[],"UserId":1,"UserName":"李刚"},长度:136 
  4. 使用DataContractJsonSerializer反序列化后的结果:UserId:1,UserName:李刚,CreateDate:1981-3-16 0:20:12,Priority:AboveNormal 
  5. 使用JsonConvert序列化后的结果:{"UserId":1,"UserName":"李刚","CreateDate":"1981-03-16T00:20:12.1875+08:00","Birthday":new Date(-277630787812),"Urls":[],"Priority":2},长度:132 
  6. 使用JsonConvert反序列化后的结果:UserId:1,UserName:李刚,CreateDate:1981-3-16 0:20:12,Priority:BelowNormal 
  7. 使用JsonConvert序列化后的结果:{"UserId":1,"UserName":"周公","CreateDate":"2003-03-16T00:20:12.40625+08:00","Birthday":new Date(290362812406),"Urls":["http://zhoufoxcn.blog.51cto.com","http://blog.csdn.net/zhoufoxcn"],"Priority":1},长度:198 
  8. 使用Linq to JSON反序列化后的结果:["http://zhoufoxcn.blog.51cto.com","http://blog.csdn.net/zhoufoxcn"] 

总结:通过上面的例子大家可以看出Newtonsoft类库提供的JSON序列化和反序列的方式更加灵活,在实际开发中周公也一直使用Newtonsoft作为JSON序列化和反序列化的不二选择。

 

周公

posted @ 2013-01-17 09:52  木子易  Views(1064)  Comments(0)    收藏  举报