Asp.Net Serialize – Deserialize

1. How to convert .NET object to JSON string
2. How to convert a JSON string to .NET object

We will be using the following Employee class
public class Employee
{
public string firstName { get; set; }
public string lastName { get; set; }
public string gender { get; set; }
public int salary { get; set; }
}

Replace < with LESSTHAN symbol and > with GREATERTHAN symbol

The following example converts List<Employee> objects to a JSON string. Serialize() method of JavaScriptSerializer class converts a .NET object to a JSON string. JavaScriptSerializer class is present in System.Web.Script.Serialization namespace.

using System;
using System.Collections.Generic;
using System.Web.Script.Serialization;

namespace Demo
{
    public partial class WebForm1 : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            Employee employee1 = new Employee
            {
                firstName = "Todd",
                lastName = "Grover",
                gender = "Male",
                salary = 50000
            };

            Employee employee2 = new Employee
            {
                firstName = "Sara",
                lastName = "Baker",
                gender = "Female",
                salary = 40000
            };

            List<Employee> listEmployee = new List<Employee>();
            listEmployee.Add(employee1);
            listEmployee.Add(employee2);

            JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();
            string JSONString = javaScriptSerializer.Serialize(listEmployee);

            Response.Write(JSONString);
        }
    }
}

Output :

[{"firstName":"Todd","lastName":"Grover","gender":"Male","salary":50000},{"firstName":"Sara","lastName":"Baker","gender":"Female","salary":40000}] 

The following example converts a JSON string to List<Employee> objects. Deserialize() method of JavaScriptSerializer class converts a JSON string to List<Employee> objects.

string jsonString = "[{\"firstName\":\"Todd\",\"lastName\":\"Grover\",\"gender\":\"Male\",\"salary\":50000},{\"firstName\":\"Sara\",\"lastName\":\"Baker\",\"gender\":\"Female\",\"salary\":40000}]";

JavaScriptSerializer javaScriptSerializer = new JavaScriptSerializer();
List<Employee> employees = (List<Employee>)javaScriptSerializer.Deserialize(jsonString, typeof(List<Employee>));

foreach(Employee employee in employees)
{
    Response.Write("First Name = " + employee.firstName + "<br/>");
    Response.Write("Last Name = " + employee.lastName + "<br/>");
    Response.Write("Gender = " + employee.gender + "<br/>");
    Response.Write("Salary = " + employee.salary + "<br/><br/>");
}

Example using NewtonSoft.Json library

using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace JSON
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Serialization");
            // 1. Serialization
           Movie movie = new Movie { Id = 1, Title = "Mission Impossible" };
            // movie is a object let us convert this to a string by using JsonConvert.SerializeObject            
            string result = JsonConvert.SerializeObject(movie);
            // Converts to string as {"Id":1,"Title":"Mission Impossible"}
            Console.WriteLine(result);

            Console.WriteLine("\nDeserialization");
            // 2. Deserialization
            Movie newMovie = JsonConvert.DeserializeObject lessthan Movie greaterthan (result);
            // Now string is converted to object            
            Console.WriteLine("Id : " + newMovie.Id);
            Console.WriteLine("Title : " + newMovie.Title);

            Console.WriteLine("\nSerialization of collection");
            // 3. Serialization of collection
            List lessthan Movie greaterthan movies = new List lessthanMovie  greaterthan {
                new Movie{ Id=1, Title="Titanic" },
                new Movie{ Id=2, Title="The martian"},
                new Movie{ Id=3, Title="Black panther"} ,
                new Movie{ Id=4, Title="Deadpool 2"} ,
            };

            string collectionResult = JsonConvert.SerializeObject(movies);
            Console.WriteLine(collectionResult);

            Console.WriteLine("\nDeserialization of collection");
            // 4. Deserialization of collection
            List lessthan Movie greaterthan  newMovies = JsonConvert.DeserializeObject lessthan List lessthan Movie greaterthan greaterthan (collectionResult);
            foreach (var item in newMovies)
            {
                Console.WriteLine("Id : "+item.Id+"\tTitle : "+item.Title);
            }
        }


        class Movie
        {
            public int Id { get; set; }
            public string Title { get; set; }
        }

    }
}