1..NET对JSON的支持介绍
(1)操作Json的DLL介绍
.NET自身有System.Runtime.Serialization.dll与System.Web.Extensions.dll，使用这两个DLL可以把对象序列化和反序列化成Json数据。也可以使用第三方的Newtonsoft.Json.dll来操作Json数据，使用它会更方便的操作Json数据，其功能也跟强一些。
(2)使用System.Web.Extensions.dll的限制
要使用System.Web.Extensions.dll必须是在Web项目中，只有在Web项目中才能引用此DLL。
2.JSON序列化和反序列化
(1)使用Newtonsoft.Json.dll实现
代码示例：
得到的Json文本：
[{"Languages":["C#","Java"],"Name":"李志伟","Sex":true},
{"Languages":["C#","C++"],"Name":"Coder2","Sex":false},
{"Languages":["C#","C++","C","Java"],"Name":"Coder3","Sex":true}]
注意：此种方式Json序列化对象时，只能序列化对象的公有成员。
(2)使用System.Web.Extensions.dll实现
代码示例：
{
public string Name;//姓名
public bool Sex;//性别，是否是男
public Person() { }//必须有此构造方法，否者无法反序列化
public Person(string name, bool sex)
{
this.Name = name;
this.Sex = sex;
}
public override string ToString()
{
return "姓名：" + this.Name + "\t性别：" + (this.Sex ? "男" : "女");
}
}
public class Programmer : Person
{
public List<string> Languages;//编程语言
public Programmer() { }//必须有此构造方法，否者无法反序列化
public Programmer(string name, bool sex, List<string> languages)
: base(name, sex)
{
this.Languages = languages;
}
public override string ToString()
{
StringBuilder str = new StringBuilder();
str.Append(base.ToString() + "\t编程语言：");
foreach (string l in this.Languages)
{
str.Append(l + " ");
}
return str.ToString();
}
}
public partial class WebForm1 : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)//Web页面的加载事件
{
List<string> languages = null;
List<Programmer> list = new List<Programmer>();
languages = new List<string>(new string[] { "C#", "Java" });
list.Add(new Programmer("李志伟", true, languages));
languages = new List<string>(new string[] { "C#", "C++" });
list.Add(new Programmer("Coder2", false, languages));
languages = new List<string>(new string[] { "C#", "C++", "C", "Java" });
list.Add(new Programmer("Coder3", true, languages));
//序列化对象
JavaScriptSerializer jsonSerialize = new JavaScriptSerializer();
string jsonStr = jsonSerialize.Serialize(list);//将对象转换成json存储
Response.Write(jsonStr + "<br>");//前台输出
//反序列化对象
list.Clear();
list = jsonSerialize.Deserialize<List<Programmer>>(jsonStr);
foreach (Programmer p in list)
{
Response.Write(p + "<br>");//前台输出
}
}
}
</div>
得到的Json文本：
[{"Languages":["C#","Java"],"Name":"李志伟","Sex":true},
{"Languages":["C#","C++"],"Name":"Coder2","Sex":false},
{"Languages":["C#","C++","C","Java"],"Name":"Coder3","Sex":true}]
注意：此种方式Json序列化对象时，除了只能序列化对象的公有成员外，被序列化的对象还必须有无参的构造方法才能被反序列化！System.Web.Extensions.dll只能在Web项目中引用，在控制台和WinFrom项目中无法引用！
(3)使用System.Runtime.Serialization.dll实现
代码示例：
public class Person
{
[DataMember(Name = "姓名")]//必须申明，否则无法序列化
private string Name;
[DataMember(Name = "性别")]//必须申明，否则无法序列化
private bool Sex;
public Person(string name, bool sex)
{
this.Name = name;
this.Sex = sex;
}
public override string ToString()
{
return "姓名：" + this.Name + "\t性别：" + (this.Sex ? "男" : "女");
}
}
[DataContract]
public class Programmer : Person
{
[DataMember(Name = "编程语言")]
private List<string> Languages;
public Programmer(string name, bool sex, List<string> languages)
: base(name, sex)
{
this.Languages = languages;
}
public override string ToString()
{
StringBuilder str = new StringBuilder();
str.Append(base.ToString() + "\t编程语言：");
foreach (string l in this.Languages)
{
str.Append(l + " ");
}
return str.ToString();
}
}
class Program
{
static void Main(string[] args)
{
string filePath = @"D:\users\lizw\桌面\ObjectJson.txt";
List<string> languages = null;
List<Programmer> list = new List<Programmer>();
languages = new List<string>(new string[] { "C#", "Java" });
list.Add(new Programmer("李志伟", true, languages));
languages = new List<string>(new string[] { "C#", "C++" });
list.Add(new Programmer("Coder2", false, languages));
languages = new List<string>(new string[] { "C#", "C++", "C", "Java" });
list.Add(new Programmer("Coder3", true, languages));
//序列化对象
DataContractJsonSerializer ser =