using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Web;
using System.Security.Cryptography;
using System.Text;
using System.IO;
using System.Net;

Namespace ConsoleApplication1
{
    class Program
    {
        //AES Encrypt
        public static string Encrypt(string toEncrypt, string key, string iv)
        {
            string encrypted = null;

            try
            {
                byte[] keyArray = UTF8Encoding.UTF8.GetBytes(key); // 128-AES key
                byte[] ivArray = Encoding.UTF8.GetBytes(iv);
                byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);

                using (RijndaelManaged rijAlg = new RijndaelManaged())
                {
                    rijAlg.KeySize = 128;
                    rijAlg.BlockSize = 128;
                    rijAlg.Key = keyArray;
                    rijAlg.IV = ivArray;
                    rijAlg.Padding = PaddingMode.PKCS7;
                    rijAlg.Mode = CipherMode.CBC;

                    ICryptoTransform encryptor = rijAlg.CreateEncryptor(rijAlg.Key, rijAlg.IV);
                    byte[] resultArray = encryptor.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

                    encrypted = Convert.ToBase64String(resultArray, 0, resultArray.Length);
                }
            }
            catch { }

            return encrypted;
        }
        static void Main(string[] args)
        {
            string dt = DateTime.UtcNow.ToString("u");
            string user = "user1";
            string blankIv = Encoding.UTF8.GetString(new byte[16]);
            string key="0123456789012345"; 
            string msg = Encrypt(dt, key, blankIv);
            System.Net.ServicePointManager.SecurityProtocol = System.Net.SecurityProtocolType.Tls12;
            string URL = "https://dmmx2.nba-hq.com/Games?date=03/01/2013&league=nba";
            string HeaderMSG = "MEDIAARCHIVE " + user + ":" + msg;
         
            WebClient serviceRequest = new WebClient();
            serviceRequest.Headers.Add("Authorization", HeaderMSG);
            string response = serviceRequest.DownloadString(new Uri(URL));
        }
    }
}