Dynamics365 Online Connection in C# Console Application

Program.cs

using System;
using Microsoft.Xrm.Tooling.Connector;

namespace Dynamics365_Console_Application
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                string authType = "AuthType=OAuth"; // AuthType is OAuth and not Office365
                string userName = "<username>@<domain>.onmicrosoft.com"; // Add your username here
                string password = "<password>"; // Add your password here
                string domainURL = "https://<domain>.crm4.dynamics.com"; // Add your Dynamics365 instance URL here 
                string universalCodes = "appid=51f81489-12ee-4a9e-aaae-a2591f45987d;redirecturi=https://callbackurl"; // Universal Id and uri
                string connectionString = string.Format("{0}{1}", authType, ";") +
                    string.Format("Username={0}{1}", userName, ";") +
                    string.Format("Password={0}{1}", password, ";") +
                    string.Format("Url={0}{1}", domainURL, ";") +
                    universalCodes;
                
                Console.WriteLine("*** Establishing connection to CRM... ***");
                CrmServiceClient client = new CrmServiceClient(connectionString);
                
                if (!client.IsReady)
                {
                    Console.WriteLine(client.LastCrmException.Message);
                    Console.WriteLine(client.LastCrmException.Source);
                    Console.WriteLine(client.LastCrmException.StackTrace);
                }
                else
                {
                    Console.WriteLine("\n*** Connection Successful! ***");
                    // Perform client operations here...
                }
                Console.WriteLine("\nPress any key to exit...");
                Console.ReadKey(true);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }

        }
    }
}