C#中Json字符串的各种应用类实例讲解

在程序中任何事物及信息都可以用对象进行描述和承载,除了比较流行的xml之外，还有一种简洁快速处理目标信息的形式那就是Json格式。

首先Json格式有自己固定的格式：例如person这个对象就可以简单的表示成{"name":"xxxx","age":12,"sex":"男"}形式。

Json格式的描述如下：先用{}包含需要表达的对象信息，在{}里使用PropertyName：Value进行对象属性的描述，同时Json字符串可以实现多层嵌套。例如：Json数据：[{PropertyName：Value,PropertyName：Value},{PropertyName：Value,PropertyName：Value}],Json嵌套格式：{PropertyName：Value,PropertyName：{PropertyName：Value,PropertyName：Value}}，理论上可以无限嵌套，但是这里建议嵌套最好不要超过3层。

对Json格式有了了解之后，那我们如何在C#中使用Json以及将已经实现的对象与Json联系起来。先个给出几个命名空间

using Newtonsoft.Json;
using System.Runtime.Serialization;
using System.ServiceModel;
using Newtonsoft.Json.Linq;
using System.IO;
using System.Runtime.Serialization.Json;

这里需要注意的是这些命名空间在 .net3.5及以上本版支持，同时必须在引用中添加 System.Runtime.Serialization.dll的引用。

这里主要使用到的类如下：

JsonSerializer ，StringWriter，StringReader ，JsonWriter，JsonConvert， DataContractJsonSerializer。

1.实现自定义类与Json进行相互转化处理：

				?

									public class Person

									  {

									    public  Person()

									    {

									    }

									    public Person(string Name, string Sex, int Age, string Address, PersonCharacter Character)

									    {

									      this.Name = Name;

									      this.Sex = Sex;

									      this.Age = Age;

									      this.Address = Address;

									      this.Character = Character;

									    }

									    public string Name { get; set; }

									    public string Sex { get; set; }

									    public int Age { get; set; }

									    public string Address { get; set; }

									    public PersonCharacter Character { get; set; }

									  }

									  public class PersonCharacter

									  {

									    public string Daode { get; set; }

									    public string Wenhua { get; set; }

									    public string Xiuyang { get; set; }

									  }

									 public void ShowConvert()

									    {

									      Person person = new Person("lanar", "男", 24, "陕西", new PersonCharacter());

									      JsonSerializer serializer = new JsonSerializer();

									StringWriter sw = new StringWriter();

									serializer.Serialize(new JsonTextWriter(sw), person );

									Console.WriteLine(sw.GetStringBuilder().ToString());

									StringReader sr = new StringReader(@"{""Name"":""ppp"", ""Age"":"12"}");

									Person p1 = (Project)serializer.Deserialize(new JsonTextReader(sr), typeof(Person));

									Console.WriteLine(p1.Name+ "=>" + p1.Age);

									}

2. 契约方式：使用System.Runtime.Serialization.dll提供的DataContractJsonSerializer或者 JsonReaderWriterFactory实现

				?

									public class Person

									  {

									    public  Person()

									    {

									    }

									    public Person(string Name, string Sex, int Age, string Address, PersonCharacter Character)

									    {

									      this.Name = Name;

									      this.Sex = Sex;

									      this.Age = Age;

									      this.Address = Address;

									      this.Character = Character;

									    }

									    [DataMember]

									    public string Name { get; set; }

									    [DataMember]

									    public string Sex { get; set; }

									    [DataMember]

									    public int Age { get; set; }

									     [DataMember]

									    public string Address { get; set; }

									    [DataMember]

									    public PersonCharacter Character { get; set; }

									  }

									  public class PersonCharacter

									  {

									    public string Daode { get; set; }

									    public string Wenhua { get; set; }

									    public string Xiuyang { get; set; }

									  }

									    public void ShowConvert()

									    {

									      Person person = new Person("许展鹏", "男", , "陕西", new PersonCharacter());

									      Person p = new Person() { Name = "四大圣地", Age = , Sex = "男", Character = new PersonCharacter() { Daode="sds", Wenhua="dasd", Xiuyang="zzz"} };

									      DataContractJsonSerializer serializer = new DataContractJsonSerializer(p.GetType());

									      string jsonText;

									      try

									      {

									        using (MemoryStream stream = new MemoryStream())

									        {

									          serializer.WriteObject(stream, p);

									          jsonText = Encoding.UTF.GetString(stream.ToArray());

									          Console.WriteLine(jsonText);

									        }

									        using (MemoryStream ms = new MemoryStream(Encoding.UTF.GetBytes(jsonText)))

									        {

									          DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(Person));

									          Person p = (Person)serializer.ReadObject(ms);

									        }

									      }

									      catch (Exception ex )

									      {

									        throw new Exception(ex.Message,ex);

									      }

									    }