JSON read/write operations with a remote server using HTTP POST in C#

In order to accomplish read/write operations with JSON, you will need a library. Json.NET is a fast and well-documented library that you can use for free.

Add Json.NET DLL file into Resources of your Visual Studio project. Then use the following code to send request to and get response in JSON format from the remote server.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Net;
using System.IO;
using Newtonsoft.Json;

public class jsonClass
{
    public void jsonOps()
    {
        // Preparing Json object to send to the remote server
        jsonLogin li = new jsonLogin();
        li.username = "your-username";
        li.password = "your-password";
        string jLoginString = JsonConvert.SerializeObject(li);

        // Create HTTP POST request
        var httpWebRequest = (HttpWebRequest)WebRequest.Create("https://www.youraddress.com");
        httpWebRequest.ContentType = "application/json";
        httpWebRequest.AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate;
        httpWebRequest.Accept = "application/json";
        httpWebRequest.Method = "POST";

        string output = "";

        // Connecting to the server. Sending request and receiving response
        using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
        {
            streamWriter.Write(jLoginString);
            streamWriter.Flush();
            streamWriter.Close();

            var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();
            using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
            {
                output = streamReader.ReadToEnd();
            }
        }

        // Reading JSON response
        JsonTextReader reader = new JsonTextReader(new StringReader(output));
        while (reader.Read())
        {
            if (reader.Value != null)
            {
                textBox1.Text = reader.Value;
            }
            else
            {
                // No value exception block
            }
        }
    }
}

public class jsonLogin
{
    public string username = "";
    public string password = "";
}

Json.NET documentation: http://james.newtonking.com/json/help/index.html