C# - Getting UnauthorizedAccessException on created Directory

Question

On my application i have a Config-FileReader - These checks on Startup, if a Temp directory (on applications folder, here the configuration will be stored as Config.json) exists, otherwise the application will create it. These steps works for a long time correctly.

After few days development, i had today create a simple File-Downloader:

    public static void Download(string url, string destination, Callback OnSuccess) {
        System.Diagnostics.Debug.WriteLine("[Download] " + url + " to " + destination + " (" + Utils.getFileName(url) + ")");
        using (var client = new WebClient())
            {
                client.Headers[HttpRequestHeader.UserAgent] = Software.getName() + "/" + Software.getVersion() + " (" + Software.getOSVersion() + "; " + Software.getOSBit() + "; " + Software.getOSVersionFull() + ")";

                client.DownloadDataCompleted += (s, e) =>
                {
                    var text = e.Result;
                    File.WriteAllText(destination, Path.Combine(destination, Utils.getFileName(url)));
                    OnSuccess((Object) Path.Combine(destination, Utils.getFileName(url)));
                };
                client.DownloadDataAsync(new Uri(url));
            }
    }

When i try to download a file to the previous created Temp directory, an UnauthorizedAccessException comes up. Curiously is: The directory was created successfully by the application and the config file will be created/readed/writed.

But when i try to download a file:

API.Download(media.URL, Software.getPath() + "Temp", OnSuccess);

Debug-Output of the Downloader:

[Download] https://c-ash.smule.com/sf/s26/arr/88/4e/48afbe6c-9aeb-4cc7-82cf-e04d5f0d6b44.mp3 to C:\Users\info\Documents\SharpDevelop Projects\SongManager\SongManager\bin\Debug\Temp (48afbe6c-9aeb-4cc7-82cf-e04d5f0d6b44.mp3)

i't gives an UnauthorizedAccessException:

System.UnauthorizedAccessException: Access to the Path "C:\Users\info\Documents\SharpDevelop Projects\SongManager\SongManager\bin\Debug\Temp" was denied.

Edit

The same problem appears, when i use another directory, which will created live before the download starts.

Edit 2

My second thinks are, thats an Threading problem, because DownloadDataAsync running on another thread. But an

Application.Current.Dispatcher.Invoke(DispatcherPriority.Background, new ThreadStart(delegate {
    File.WriteAllText(destination, Path.Combine(destination, Utils.getFileName(url)));
}));

won't fix the problem.

Answer 1

I call shenanigans

File.WriteAllText Method (String, String)

Parameters

• path

  • Type: System.String
  • The file to write to.

• contents

  • Type: System.String
  • The string to write to the file.

Your Code

client.DownloadDataCompleted += (s, e) =>
         {
            var text = e.Result;
            // look at your parameters 
            File.WriteAllText(destination, Path.Combine(destination, Utils.getFileName(url)));
            OnSuccess((Object)Path.Combine(destination, Utils.getFileName(url)));
         };

You are calling File.WriteAllText on a directory, and passing the combined path as the contents.

The error should be,

"Step away from the keyboard young jedi and make your self a coffee! A directory is not a file and you have no business writing to one"