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WebClient.OnDownloadProgressChanged(DownloadProgressChangedEventArgs) Method

Definition

Raises the DownloadProgressChanged event.

protected:
 virtual void OnDownloadProgressChanged(System::Net::DownloadProgressChangedEventArgs ^ e);
protected virtual void OnDownloadProgressChanged (System.Net.DownloadProgressChangedEventArgs e);
abstract member OnDownloadProgressChanged : System.Net.DownloadProgressChangedEventArgs -> unit
override this.OnDownloadProgressChanged : System.Net.DownloadProgressChangedEventArgs -> unit
Protected Overridable Sub OnDownloadProgressChanged (e As DownloadProgressChangedEventArgs)

Parameters

Examples

The following code example shows an implementation of this method that can be customized by a class derived from WebClient.

virtual void OnDownloadProgressChanged( DownloadProgressChangedEventArgs ^ e ) override
{
   // Here you can perform any custom actions before the event is raised
   // and event handlers are called...
   WebClient::OnDownloadProgressChanged( e );

   // Here you can perform any post event actions...
}
protected override void OnDownloadProgressChanged (DownloadProgressChangedEventArgs e)
{
    // Here you can perform any custom actions before the event is raised
    // and event handlers are called...

    base.OnDownloadProgressChanged (e);

    // Here you can perform any post event actions...
}

Remarks

Caution

WebRequest, HttpWebRequest, ServicePoint, and WebClient are obsolete, and you shouldn't use them for new development. Use HttpClient instead.

Classes that inherit from this class can override this method to perform additional tasks when the DownloadProgressChanged event occurs.

Raising an event invokes the event handler through a delegate. For more information, see Handling and Raising Events.

The OnDownloadProgressChanged method also allows derived classes to handle the event without attaching a delegate. This is the preferred technique for handling the event in a derived class.

Notes to Inheritors

When overriding OnDownloadProgressChanged(DownloadProgressChangedEventArgs) in a derived class, be sure to call the base class' OnDownloadProgressChanged(DownloadProgressChangedEventArgs) method so that registered delegates receive the event.

Applies to