Output data in JSON format

From the server, we may need to push data to variety of clients in JSON (JavaScript Object Notation) format.As an example, the server is a web server and type of the application is a web services.The client may be a PHP/ASP Net/[XYZ...] application or Mobile app.To generate a JSON data from Data, we can use the "JavaScriptSerializer" method from the library of  "System.Web.Script.Serialization" of .NET framework.Here is the code example.

C#
===
using System;
using System.Collections.Generic;
using System.Web.Script.Serialization;
using System.Data;
using System.Text;
namespace TESTConsoleApplicatio
{
    public class JSONCLASS
    {
        public static string GetJSONData(DataTable dt)
        {
        
          StringBuilder sb = new StringBuilder();
        
          List> result = new List>();
       
          foreach (DataRow dr in dt.Rows)
          {
              Dictionary drow = new Dictionary();
              for (int i = 0; i < dt.Columns.Count; i++)
              {
               
                  drow.Add(dt.Columns[i].ColumnName, dr[i]);
              }
              result.Add(drow);
          }


          JavaScriptSerializer js = new JavaScriptSerializer();  
          string jsonString = js.Serialize(result);
            //OUTPUT JSON
            //{"product":[{\"ID\":1001,\"name\":\"Book 1\",\"category\":\"Category 1\"},
            //             {\"ID\":2001,\"name\":\"Book 2\",\"category\":\"Category 2\"},
            //              {\"ID\":1002,\"name\":\"Book 22\",\"category\":\"Category 1\"} ]}     

          return "{\""  + dt.TableName + "\":" + jsonString + "}";

        }

    }
}

========
INPUT/OUTPUT

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Data;

namespace TESTConsoleApplicatio
{
    class Program
    {
        static void Main(string[] args)
        {
             //INPUT DATA.May be we can get data from database or other sources
 
            DataTable dt = new DataTable("product");
            dt.Columns.Add("ID",typeof( int));                     
            dt.Columns.Add("name");
            dt.Columns.Add("category");

            DataRow rw = dt.NewRow();
            rw["ID"] = 1001;
            rw["name"] = "Book 1";
            rw["category"] = "Category 1";
            dt.Rows.Add(rw);
               
                 rw = dt.NewRow();
                rw["ID"] = 2001;
                rw["name"] = "Book 2";
                rw["category"] = "Category 2";
                dt.Rows.Add(rw);

             rw = dt.NewRow();
                rw["ID"] = 1002;
                rw["name"] = "Book 22";
                rw["category"] = "Category 1";
                dt.Rows.Add(rw);

           

            string jsonOutput = JSONCLASS.GetJSONData(dt);
            
               //We can out put data as a web services
            Console.Write(jsonOutput);
            Console.ReadLine();
         
           
           
           
               
           
        }
    }
}