UploadFileCompletedEventHandler Delegate


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Represents the method that will handle the UploadFileCompleted event of a WebClient.

Namespace:   System.Net
Assembly:  System (in System.dll)

public delegate void UploadFileCompletedEventHandler(
	object sender,
	UploadFileCompletedEventArgs e


Type: System.Object

The source of the event.

Type: System.Net.UploadFileCompletedEventArgs

A UploadFileCompletedEventArgs that contains event data.

When you create a UploadFileCompletedEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see NIB: Events and Delegates.

The following code example demonstrates asynchronously uploading a file.

// Sample call: UploadFileInBackground("http://www.contoso.com/fileUpload.aspx", "data.txt")
public static void UploadFileInBackground (string address, string fileName)
    System.Threading.AutoResetEvent waiter = new System.Threading.AutoResetEvent (false);
    WebClient client = new WebClient ();
    Uri uri = new Uri(address);
    string method = "POST";

    // Specify that that UploadFileCallback method gets called
    // when the file upload completes.
    client.UploadFileCompleted += new UploadFileCompletedEventHandler (UploadFileCallback);
    client.UploadFileAsync (uri, method, fileName, waiter);

    // Block the main application thread. Real applications
    // can perform other tasks while waiting for the upload to complete.
    waiter.WaitOne ();
    Console.WriteLine ("File upload is complete.");

The following method is called when the upload completes.

private static void UploadFileCallback (Object sender, UploadFileCompletedEventArgs e)
    System.Threading.AutoResetEvent waiter = (System.Threading.AutoResetEvent)e.UserState;;
        string reply = System.Text.Encoding.UTF8.GetString (e.Result);

        Console.WriteLine (reply);
        // If this thread throws an exception, make sure that
        // you let the main application thread resume.
        waiter.Set ();

.NET Framework
Available since 2.0
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