如何在.net上为WebClient设置TimeOut？

Question

I download some file but I also want to set timeout for webclient. As I see there is no change just We can use overriding WebRequest. I already did but It doesnt work. I mean tht overriding of GetWebRequest method doesnt work.. Here are my codes

  public class VideoDownloader : Downloader
{
    /// <summary>
    /// Initializes a new instance of the <see cref="VideoDownloader"/> class.
    /// </summary>
    /// <param name="video">The video to download.</param>
    /// <param name="savePath">The path to save the video.</param>
    public VideoDownloader(VideoInfo video, string savePath)
        : base(video, savePath)
    { }


    /// <summary>
    /// Starts the video download.
    /// </summary>
    public override void Execute()
    {
        // We need a handle to keep the method synchronously
        var handle = new ManualResetEvent(false);

        var client = new WebClient();


        client.DownloadFileCompleted += (sender, args) => handle.Set();
        client.DownloadProgressChanged += (sender, args) =>
        this.OnProgressChanged(new ProgressEventArgs(args.ProgressPercentage));

        this.OnDownloadStarted(EventArgs.Empty);

      client.DownloadFileAsync(new Uri(this.Video.DownloadUrl), this.SavePath);

        handle.WaitOne();
        handle.Close();


        this.OnDownloadFinished(EventArgs.Empty);
    }

    protected override WebRequest GetWebRequest(Uri address)
    {
        WebRequest w = base.GetWebRequest(address);
        w.Timeout = 10*1000; // 20 * 60 * 1000;
        return w;

    }

}

And the Download class

 public abstract class Downloader: WebClient
{
    /// <summary>
    /// Initializes a new instance of the <see cref="Downloader"/> class.
    /// </summary>
    /// <param name="video">The video to download/convert.</param>
    /// <param name="savePath">The path to save the video/audio.</param>
    protected Downloader(VideoInfo video, string savePath)
    {
        this.Video = video;
        this.SavePath = savePath;
    }

    protected override WebRequest GetWebRequest(Uri address)
    {
        WebRequest w = base.GetWebRequest(address);
        w.Timeout = 10 * 1000; // 20 * 60 * 1000;
        return w;

    }

    /// <summary>
    /// Occurs when the download finished.
    /// </summary>
    public event EventHandler DownloadFinished;

    /// <summary>
    /// Occurs when the download is starts.
    /// </summary>
    public event EventHandler DownloadStarted;

    /// <summary>
    /// Occurs when the progress has changed.
    /// </summary>
    public event EventHandler<ProgressEventArgs> ProgressChanged;

    /// <summary>
    /// Gets the path to save the video/audio.
    /// </summary>
    public string SavePath { get; private set; }

    /// <summary>
    /// Gets the video to download/convert.
    /// </summary>
    public VideoInfo Video { get; private set; }

    /// <summary>
    /// Starts the work of the <see cref="Downloader"/>.
    /// </summary>
    public abstract void Execute();

    protected void OnDownloadFinished(EventArgs e)
    {
        if (this.DownloadFinished != null)
        {
            this.DownloadFinished(this, e);
        }

    }

    protected void OnDownloadStarted(EventArgs e)
    {
        if (this.DownloadStarted != null)
        {
            this.DownloadStarted(this, e);
        }
    }

    protected void OnProgressChanged(ProgressEventArgs e)
    {
        if (this.ProgressChanged != null)
        {
            this.ProgressChanged(this, e);
        }
    }
}

Where is my mistake ? Note: I want do download asynchrony

Answer 1

From the MSDN Doc:

The Timeout property affects only synchronous requests made with the GetResponse method. To time out asynchronous requests, use the Abort method.

So if you are going to do an asynchronous request, I think you need to manage a timer of your own, and call .Abort() on the instance after whatever period of time.

There is some sample code showing this on this MSDN page for the .Abort() method.