Check out example codes for "http post request login example asp.net c#". It will help you in understanding the concepts better.

Code Example 1

using System;
using System.Text;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Threading.Tasks;

namespace HttpClientAuth
{
    class Program
    {
        static async Task Main(string[] args)
        {
            var userName = "user7";
            var passwd = "passwd";
            var url = "https://httpbin.org/basic-auth/user7/passwd";

            using var client = new HttpClient();

            var authToken = Encoding.ASCII.GetBytes($"{userName}:{passwd}");
            client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic",
                    Convert.ToBase64String(authToken));

            var result = await client.GetAsync(url);

            var content = await result.Content.ReadAsStringAsync();
            Console.WriteLine(content);
        }
    }
}

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