DownloadProgressChangedEventHandler Delegate
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DownloadProgressChangedEventHandler Delegate

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

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

public delegate void DownloadProgressChangedEventHandler (
	Object sender,
	DownloadProgressChangedEventArgs e
/** @delegate */
public delegate void DownloadProgressChangedEventHandler (
	Object sender, 
	DownloadProgressChangedEventArgs e
Not applicable.



The source of the event.


A DownloadProgressChangedEventArgs containing event data.

When you create a DownloadProgressChangedEventHandler 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 Events and Delegates. Events and Delegates


If the server does not send the size of the downloaded file (such as in the case of a passive FTP connection), ProgressPercentage may always be zero.

The following code example demonstrates setting an event handler for the WebClient.DownloadProgressChanged event.

// Sample call : DownLoadFileInBackground2 ("");
public static void DownLoadFileInBackground2 (string address)
    WebClient client = new WebClient ();
    Uri uri = new Uri(address);

    // Specify that the DownloadFileCallback method gets called
    // when the download completes.
    client.DownloadFileCompleted += new AsyncCompletedEventHandler (DownloadFileCallback2);
    // Specify a progress notification handler.
    client.DownloadProgressChanged += new DownloadProgressChangedEventHandler(DownloadProgressCallback);
    client.DownloadFileAsync (uri, "serverdata.txt");

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0

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