Domanda Downloader C#

[†Zero†]

ciao a tutti oggi ho fatto questo downloader però mi da errore...alla linea rossa e mi sono scervellato per capire cosa c'e che non va ma non ci sono riuscito...aiutatemi!

namespace DownloadManager2
{
    public partial class Form1 : Form
    {
        private Thread thrDownload;
        private Stream strResponse;
        private Stream strLocal;
        private HttpWebRequest webRequest;
        private HttpWebResponse webResponse;
        private static int PercentProgress;
        private delegate void UpdateProgessCallback(Int64 BytesRead, Int64 TotalBytes);
        bool goPause = false;

        public Form1()
        {
            InitializeComponent();
        }

        private void btnDownload_Click(object sender, EventArgs e)
        {
            if (thrDownload != null && thrDownload.ThreadState == ThreadState.Running)
            {
                MessageBox.Show("Impossibile avviare download. Aspettare che sia completato il primo", "Download in progress", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
            else
            {
                lblProgress.Text = "Avviando Download";
                thrDownload = new Thread(new ParameterizedThreadStart(Download));
                thrDownload.Start(0);
                btnPauseResume.Enabled = true;
                btnPauseResume.Text = "Pausa";
            }
        }

        private void UpdateProgress(Int64 BytesRead, Int64 TotalBytes)
        {
            PercentProgress = Convert.ToInt32((BytesRead * 100) / TotalBytes);
            prgDownload.Value = PercentProgress;
            lblProgress.Text = "Scaricato " + BytesRead + " di " + TotalBytes + " (" + PercentProgress + "%)";
        }

        private void Download(object startPoint)
        {
            try
            {
                int startPointInt = Convert.ToInt32(startPoint);
                webRequest = (HttpWebRequest)WebRequest.Create(txtUrl.Text);
                webRequest.AddRange(startPointInt);

                webRequest.Credentials = CredentialCache.DefaultCredentials;
                [COLOR="#ff0000"]webResponse = (HttpWebResponse)webRequest.GetResponse();[/COLOR]
                Int64 fileSize = webResponse.ContentLength;
                
                strResponse = webResponse.GetResponseStream();

                if (startPointInt == 0)
                {
                    strLocal = new FileStream(txtPath.Text, FileMode.Create, FileAccess.Write, FileShare.None);
                }
                else
                {
                    strLocal = new FileStream(txtPath.Text, FileMode.Append, FileAccess.Write, FileShare.None);
                }
                
                int bytesSize = 0;
                byte[] downBuffer = new byte[2048];

                while ((bytesSize = strResponse.Read(downBuffer, 0, downBuffer.Length)) > 0)
                {
                    strLocal.Write(downBuffer, 0, bytesSize);
                    this.Invoke(new UpdateProgessCallback(this.UpdateProgress), new object[] { strLocal.Length, fileSize + startPointInt });

                    if (goPause == true)
                    {
                        break;
                    }
                }
            }
            finally
            {
                strResponse.Close();
                strLocal.Close();
            }
        }

        private void btnStop_Click(object sender, EventArgs e)
        {
            thrDownload.Abort();
            webResponse.Close();
            strResponse.Close();
            strLocal.Close();
            prgDownload.Value = 0;
            lblProgress.Text = "Download stoppato";
            btnPauseResume.Enabled = false;
        }

        private void btnPauseResume_Click(object sender, EventArgs e)
        {
            if (thrDownload != null)
            {
                if (

 

[eximus]

                     // Create a new WebRequest Object to the mentioned URL.
            WebRequest myWebRequest=WebRequest.Create("http://www.contoso.com");
            Console.WriteLine("\nThe Timeout time of the request before setting is : {0} milliseconds",myWebRequest.Timeout);

            // Set the 'Timeout' property in Milliseconds.
            myWebRequest.Timeout=10000;

            // This request will throw a WebException if it reaches the timeout limit before it is able to fetch the resource.
                     WebResponse myWebResponse=myWebRequest.GetResponse();

la sintassi corretta è questa
fonte: msdn

 

[†Zero†]

grazie