C# Async File Download throws System.IO Exception

Question

I am currently programming a html parser for a little research project. First the html page is downloaded, so it can be analyzed later on. I am using a Async Downloader which throws an System.IO Exception at me , which I don't understand.

    public void downloadFile(String address)
    {
        string pfad = @"c:\Greyhound";
        if(!Directory.Exists(pfad))
        {
            Directory.CreateDirectory(pfad);
        }
        WebClient down = new WebClient();
        down.DownloadProgressChanged += new DownloadProgressChangedEventHandler(ProgressChanged);
        down.DownloadFileAsync(new Uri(address), @"c:\Greyhound\page.html");
    }

    private void ProgressChanged(object sender, DownloadProgressChangedEventArgs e)
    {
        MainWindow mainwindow = new MainWindow();
        mainwindow.UpdateProgress(e.ProgressPercentage);

    }

The MainWindows.cs

private void GoButton_Click(object sender, EventArgs e)
    {
        Downloader down = new Downloader();
        down.downloadFile(Convert.ToString(AddressBox.Text));
    }
    public void UpdateProgress(int percentage)
    {
        progressBar.Value = percentage; 
    }

When I click "Go" the Folder is created and the Download starts and finishes! I checked it. The File exists and is alright with the right content. But when I move the mouse over the progressbar the waiting circle appears. The Debugger tells me , that it throws a IO Exception here:

down.DownloadFileAsync(new Uri(address), @"c:\Greyhound\page.html");

And tells me: "Specified registry key does not exist" But the path is not wrong. I am downloading "http://de.selfhtml.org/html/text/anzeige/h1_6.htm" by the way.

C# Async File Download throws System.IO Exception

0 Answers0