我们用到的类库为：Newtonsoft.Json，通过VS工具中NuGet程序包可以下载。

一：对象转json-序列化

public class Student
{
    public int ID { get; set; }
    public string Name { get; set; }
    public int Age { get; set; }
}
    //第一种：单一实体类
    Student s = new Student();
    s.Age = 18;
    s.ID = 1;
    s.Name = "张三";
    string json = Newtonsoft.Json.javaScriptConvert.SerializeObject(s);//序列化对象（对象转json）

    //第二种：List<T>泛型 和上边方法相同
    List<Student> list = new List<Student>();
    for (int i = 1; i < 5; i++)
    {
        Student stu = new Student();
        stu.Age = i + 12;
        stu.ID = i;
        stu.Name = "No."+i.ToString();
        list.Add(stu);
    }
    json = Newtonsoft.Json.JavascriptConvert.SerializeObject(list);

二：json转对象 - 反序列化

    //json只有一条数据
    JavaScriptObject obj = (JavaScriptObject)JavaScriptConvert.DeserializeObject(json);
    string Name = obj["Name"].ToString();//取出某一字段
    Response.Write(Name);
    //json只有一条数据
    Student ms = (Student)JavaScriptConvert.DeserializeObject(JavaScriptConvert.SerializeObject(obj), typeof(Student));//json转对象
    Response.Write(ms.Name);

    //json有多条数据
    JavaScriptArray javascript = (JavaScriptArray)JavaScriptConvert.DeserializeObject(json);
    List<Student> slist = new List<Student>();
    for (int i = 0; i < javascript.Count; i++)
    {
        JavaScriptObject temp = (JavaScriptObject)javascript[i];
        Student model = (Student)JavaScriptConvert.DeserializeObject(JavaScriptConvert.SerializeObject(temp), typeof(Student));
        slist.Add(model);
    }

    //4.0方法
    List<Student> slist = JsonConvert.DeserializeObject<List<Student>>(json);

    Response.Write(slist[0].Name);