序列化是将对象转换成另一种格式（XML、json、二进制byte[]）

.NET中有三种常用的JSON序列化的类，分别是：

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：），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：

public static void JsonConvertDemo() { User user = new User { UserId = 1, UserName = "李刚", CreateDate = DateTime.Now.AddYears(-30), Birthday = DateTime.Now.AddYears(-50), Priority = Priority.BelowNormal, Salary = 5000 }; //JsonConvert类在Newtonsoft.Json.Net35.dll中，注意到http://下载这个dll并添加这个引用 //JSON序列化 string result = JsonConvert.SerializeObject(user); Console.WriteLine("使用JsonConvert序列化后的结果：{0},长度：{1}", result, result.Length); //JSON反序列化 user = JsonConvert.DeserializeObject<User>(result); 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); } public static void JsonConvertLinqDemo() { 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> { "", "" } }; //JsonConvert类在Newtonsoft.Json.Net35.dll中，注意到http://下载这个dll并添加这个引用 //JSON序列化 string result = JsonConvert.SerializeObject(user); Console.WriteLine("使用JsonConvert序列化后的结果：{0},长度：{1}", result, result.Length); //使用Linq to JSON JObject jobject = JObject.Parse(result); JToken token = jobject["Urls"]; List<string> urlList = new List<string>(); foreach (JToken t in token) { urlList.Add(t.ToString()); } Console.Write("使用Linq to JSON反序列化后的结果：["); for (int i = 0; i < urlList.Count - 1;i++ ) { Console.Write(urlList[i] + ","); } Console.WriteLine(urlList[urlList.Count - 1] + "]"); }

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。
该实例完整代码：

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Web.Script.Serialization; using System.Runtime.Serialization.Json; using System.IO; using System.Runtime.Serialization; using Newtonsoft.Json; using Newtonsoft.Json.Linq; using Newtonsoft.Json.Converters; namespace JSONDemo { class Program { static void Main(string[] args) { JavaScriptSerializerDemo(); DataContractJsonSerializerDemo(); JsonConvertDemo(); JsonConvertLinqDemo(); Console.ReadLine(); } public static void JavaScriptSerializerDemo() { User user = new User { UserId = 1, UserName = "李刚", CreateDate = DateTime.Now.AddYears(-30),Birthday=DateTime.Now.AddYears(-50), Priority = Priority.Highest, Salary = 500000 }; //JavaScriptSerializer类在System.Web.Extensions.dll中，注意添加这个引用 JavaScriptSerializer serializer = new JavaScriptSerializer(); //JSON序列化 string result=serializer.Serialize(user); Console.WriteLine("使用JavaScriptSerializer序列化后的结果：{0},长度：{1}", result, result.Length); //JSON反序列化 user = serializer.Deserialize<User>(result); 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); } public static void DataContractJsonSerializerDemo() { User user = new User { UserId = 1, UserName = "李刚", CreateDate = DateTime.Now.AddYears(-30), Birthday = DateTime.Now.AddYears(-50), Priority = Priority.AboveNormal, Salary = 50000 }; string result = string.Empty; //DataContractJsonSerializer类在System.ServiceModel.Web.dll中，注意添加这个引用 DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(User)); using (MemoryStream stream = new MemoryStream()) { //JSON序列化 serializer.WriteObject(stream, user); result = Encoding.UTF8.GetString(stream.ToArray()); Console.WriteLine("使用DataContractJsonSerializer序列化后的结果：{0},长度：{1}", result, result.Length); } //JSON反序列化 byte[] buffer = Encoding.UTF8.GetBytes(result); using (MemoryStream stream = new MemoryStream(buffer)) { user = serializer.ReadObject(stream) as User; 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); } } public static void JsonConvertDemo() { User user = new User { UserId = 1, UserName = "李刚", CreateDate = DateTime.Now.AddYears(-30), Birthday = DateTime.Now.AddYears(-50), Priority = Priority.BelowNormal, Salary = 5000 }; //JsonConvert类在Newtonsoft.Json.Net35.dll中，注意到http://下载这个dll并添加这个引用 //JSON序列化 string result = JsonConvert.SerializeObject(user); Console.WriteLine("使用JsonConvert序列化后的结果：{0},长度：{1}", result, result.Length); //JSON反序列化 user = JsonConvert.DeserializeObject<User>(result); 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); } public static void JsonConvertLinqDemo() { 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> { "", "" } }; //JsonConvert类在Newtonsoft.Json.Net35.dll中，注意到http://下载这个dll并添加这个引用 //JSON序列化 string result = JsonConvert.SerializeObject(user); Console.WriteLine("使用JsonConvert序列化后的结果：{0},长度：{1}", result, result.Length); //使用Linq to JSON JObject jobject = JObject.Parse(result); JToken token = jobject["Urls"]; List<string> urlList = new List<string>(); foreach (JToken t in token) { urlList.Add(t.ToString()); } Console.Write("使用Linq to JSON反序列化后的结果：["); for (int i = 0; i < urlList.Count - 1;i++ ) { Console.Write(urlList[i] + ","); } Console.WriteLine(urlList[urlList.Count - 1] + "]"); } } [DataContract] public class User { /// <summary> /// 编号 /// </summary> [DataMember] public int UserId { get; set; } /// <summary> /// 用户名 /// </summary> [DataMember] public string UserName { get; set; } /// <summary> /// 创建时间 /// </summary> [DataMember] [JsonConverter(typeof(IsoDateTimeConverter))] public DateTime CreateDate { get; set; } /// <summary> /// 生日 /// </summary> [DataMember] [JsonConverter(typeof(JavaScriptDateTimeConverter))] public DateTime Birthday { get; set; } /// <summary> /// 相关URL /// </summary> [DataMember] public List<string> Urls { get; set; } /// <summary> /// 薪水 /// </summary> [ScriptIgnore]//使用JavaScriptSerializer序列化时不序列化此字段 [IgnoreDataMember]//使用DataContractJsonSerializer序列化时不序列化此字段 [JsonIgnore]//使用JsonConvert序列化时不序列化此字段 public int Salary { get; set; } /// <summary> /// 权利级别 /// </summary> [DataMember] public Priority Priority { get; set; } public User() { Urls = new List<string>(); } } /// <summary> /// 权利级别 /// </summary> public enum Priority:byte { Lowest=0x1, BelowNormal=0x2, Normal=0x4, AboveNormal=0x8, Highest=0x16 } }

运行结果：