private void btnTestDownload_Click(object sender, EventArgs e)

{

    backgroundWorker1.RunWorkerAsync();

}

private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)

{

    // the URL to download the file from

    string sUrlToReadFileFrom = "http://devtoolshed.googlepages.com/filezilla_download.exe";

    // the path to write the file to

    string sFilePathToWriteFileTo = "C:\\filezilla_download.exe";

    // first, we need to get the exact size (in bytes) of the file we are downloading

    Uri url = new Uri(sUrlToReadFileFrom);

    System.Net.HttpWebRequest request = (System.Net.HttpWebRequest)System.Net.WebRequest.Create(url);

    System.Net.HttpWebResponse response = (System.Net.HttpWebResponse)request.GetResponse();

    response.Close();

    // gets the size of the file in bytes

    Int64 iSize = response.ContentLength;

    // keeps track of the total bytes downloaded so we can update the progress bar

    Int64 iRunningByteTotal = 0;

    // use the webclient object to download the file

    using (System.Net.WebClient client = new System.Net.WebClient())

    {

        // open the file at the remote URL for reading

        using (System.IO.Stream streamRemote = client.OpenRead(new Uri(sUrlToReadFileFrom)))

        {

            // using the FileStream object, we can write the downloaded bytes to the file system

            using (Stream streamLocal = new FileStream(sFilePathToWriteFileTo, FileMode.Create, FileAccess.Write, FileShare.None))

            {

                // loop the stream and get the file into the byte buffer

                int iByteSize = 0;

                byte[] byteBuffer = new byte[iSize];

                while ((iByteSize = streamRemote.Read(byteBuffer, 0, byteBuffer.Length)) > 0)

                {

                    // write the bytes to the file system at the file path specified

                    streamLocal.Write(byteBuffer, 0, iByteSize);

                    iRunningByteTotal += iByteSize;

                    // calculate the progress out of a base "100"

                    double dIndex = (double)(iRunningByteTotal);

                    double dTotal = (double)byteBuffer.Length;

                    double dProgressPercentage = (dIndex / dTotal);

                    int iProgressPercentage = (int)(dProgressPercentage * 100);

                    // update the progress bar

                    backgroundWorker1.ReportProgress(iProgressPercentage);

                }

                // clean up the file stream

                streamLocal.Close();

            }

            // close the connection to the remote server

            streamRemote.Close();

        }

    }

}

private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)

{

    progressBar1.Value = e.ProgressPercentage;

}

private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)

{

    MessageBox.Show("File download complete");

}