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In C# how can i get list new URLs that is redirected from website?
this.converts = new Thread(new ThreadStart(this.convert));
this.converts.Start();

private void convert()
        {   //I have to add this or it gives //

            Control.CheckForIllegalCrossThreadCalls = false;

            // Cross-thread operation not valid error//


            string[] lines = this.textBox1.Lines;
            for (int i = 0; i < lines.Length; i++)
            {

                if ((lines[i] != "") && lines[i].Contains("http://"))
                {
                    string str = this.Get_Redirected_link(user, pass, lines[i]);
                    this.textBox2.Text = this.textBox2.Text + str + "rn";
                }
            }
}

private string Get_Redirected_link(string username, string password, string url)
        {
            WebRequest request = WebRequest.Create(url);
            string s = username + ":" + password;
            CredentialCache cache = new CredentialCache();
            cache.Add(new Uri(url), "Basic", new NetworkCredential(username, password));
            request.Credentials = cache;
            request.Headers.Add("Authorization", "Basic " + Convert.ToBase64String(new ASCIIEncoding().GetBytes(s)));
            try
            {
                return request.GetResponse().ResponseUri.AbsoluteUri;
            }
            catch
            {
                return "error";
            }
        }