HttpWebRequest Login

Dim cookieCon As CookieContainer

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        Dim postData As String = "vb_login_username=" & TextBox1.Text & "&vb_login_password=" & TextBox2.Text & "&cookieuser=1&s=&securitytoken=1445179991-b75a6c52d0a5a816f245a4253bd8c59bfcf13204&do=login&vb_login_md5password=&vb_login_md5password_utf="
        Dim tempCookie As New CookieContainer
        Dim encoding As New UTF8Encoding
        Dim byteData As Byte() = encoding.GetBytes(postData)

        Dim postReq As Net.HttpWebRequest = DirectCast(WebRequest.Create("http://www.elitepvpers.com/forum/login.php?do=login"), Net.HttpWebRequest)
        postReq.Method = "POST"
        postReq.KeepAlive = True
        postReq.CookieContainer = tempCookie
        postReq.ContentType = "application/x-www-form-urlencoded"
        postReq.Referer = "http://www.elitepvpers.com/forum/login.php?do=login"
        postReq.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:41.0) Gecko/20100101 Firefox/41.0"
        postReq.ContentLength = byteData.Length


        Dim postreqstream As Stream = postReq.GetRequestStream()
        postreqstream.Write(byteData, 0, byteData.Length)
        postreqstream.Close()

        Dim postresponse As HttpWebResponse

        postresponse = DirectCast(postReq.GetResponse(), HttpWebResponse)
        tempCookie.Add(postresponse.Cookies)
        cookieCon = tempCookie

        Dim postreqreader As New StreamReader(postresponse.GetResponseStream())

        Dim thepage As String = postreqreader.ReadToEnd

        RichTextBox1.Text = thepage
    End Sub

using System;
using System.Text;
using System.IO;
using System.Net;
using System.Text.RegularExpressions;

using System.Security.Cryptography;

public class Http
    {
        public static CookieContainer stdCookie = new CookieContainer();
        public static CookieContainer emptyCookie = null;

        public static string LocationUrl = "";

        public static string Post(string URL, string post, ref CookieContainer cookie)
        {
            string result;
            try
            {
                HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(URL);
                httpWebRequest.Method = "POST";
                httpWebRequest.CookieContainer = cookie;
                httpWebRequest.ContentType = "application/x-www-form-urlencoded";
                byte[] bytes = Encoding.Default.GetBytes(post);
                httpWebRequest.ContentLength = (long)bytes.Length;
                Stream stream = httpWebRequest.GetRequestStream();
                stream.Write(bytes, 0, bytes.Length);
                stream.Close();
                httpWebRequest.KeepAlive = true;
                httpWebRequest.AllowAutoRedirect = true;
                httpWebRequest.PreAuthenticate = true;
                HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
                stream = httpWebResponse.GetResponseStream();
                StreamReader streamReader = new StreamReader(stream);
                string text = streamReader.ReadToEnd();
                streamReader.Close();
                stream.Close();
                LocationUrl = httpWebResponse.ResponseUri.OriginalString;
                httpWebResponse.Close();
                result = text;
            }
            catch
            {
                result = "";
            }
            return result;
        }

        public static string Get(string URL, ref CookieContainer cookie)
        {
            string result;
            try
            {
                HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(URL);
                httpWebRequest.Method = "GET";
                httpWebRequest.CookieContainer = cookie;
                httpWebRequest.ContentType = "application/x-www-form-urlencoded";
                httpWebRequest.Proxy.Credentials = CredentialCache.DefaultCredentials;
                HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
                Stream responseStream = httpWebResponse.GetResponseStream();
                StreamReader streamReader = new StreamReader(responseStream);
                string text = streamReader.ReadToEnd();
                streamReader.Close();
                responseStream.Close();
                LocationUrl = httpWebResponse.ResponseUri.OriginalString;
                httpWebResponse.Close();
                result = text;
            }
            catch
            {
                result = "";
            }
            return result;
        }

        public static string UrlEncode(string s)
        {
            return Uri.EscapeUriString(s);
        }

        public static string StringBetween(string s, string start, string end)
        {
            string ret = "";
            try
            {
                ret = Regex.Match(s, start + "(.*)" + end).Groups[1].Value;
            }
            catch
            {
            }
            return ret;
        }

        public static string MD5(string s)
        {
            MD5CryptoServiceProvider provider = new MD5CryptoServiceProvider();
            byte[] hash = provider.ComputeHash(Encoding.UTF8.GetBytes(s));
            provider.Dispose();
            return BitConverter.ToString(hash).Replace("-", "").ToLower();
        }

        public static string Base64Decode(string s)
        {
            return Encoding.UTF8.GetString(Convert.FromBase64String(s));
        }

        public static string Base64Encode(string s)
        {
            return Convert.ToBase64String(Encoding.UTF8.GetBytes(s));
        }
    }

    Private Sub btnStart_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnStart.Click
        Dim cookieCon As New CookieContainer
        Dim request As HttpWebRequest = DirectCast(HttpWebRequest.Create("https://forum.die-staemme.de/login.php?do=login"), HttpWebRequest)
        Dim username As String = TextBox1.Text
        Dim password As String = TextBox2.Text
        Dim post As String = "vb_login_username=" & username & "&vb_login_password=" & password & "&vb_login_password_hint=Kennwort&s=&securitytoken=guest&do=login&vb_login_md5password=&vb_login_md5password_utf="

        POST_________LOGIN_________________________

        request.Method = "POST"
        request.CookieContainer = cookieCon
        request.UserAgent = "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:41.0) Gecko/20100101 Firefox/41.0"
        request.ContentType = "application/x-www-form-urlencoded"

        Dim byteArr() As Byte = Encoding.Default.GetBytes(post)
        request.ContentLength = byteArr.Length

        Dim dataStream As Stream = request.GetRequestStream()
        dataStream.Write(byteArr, 0, byteArr.Length)


        Dim response As HttpWebResponse = DirectCast(request.GetResponse(), HttpWebResponse)

        Dim reader As New StreamReader(response.GetResponseStream())
        Dim seitenQuelltext As String = reader.ReadToEnd()

        If seitenQuelltext.Contains("Weiterleitung . . .") Then
            Label3.Text = "Eingeloggt!"
            seitenQuelltext = ""
        Else
            Label3.Text = "Fehler"
        End If


        GET____AUF HAUPTSEITTE_______________________________

        request = DirectCast(HttpWebRequest.Create("https://forum.die-staemme.de/forum.php"), HttpWebRequest)
        request.CookieContainer = cookieCon
        request.KeepAlive = True

        response = DirectCast(request.GetResponse(), HttpWebResponse)
        reader = New StreamReader(response.GetResponseStream())
        seitenQuelltext = reader.ReadToEnd()


        If seitenQuelltext.Contains("Abmelden") Then
            Label4.Text = "OK"
        Else
            Label4.Text = "Fehler"
        End If


    End Sub