WebClient.OnUploadProgressChanged(UploadProgressChangedEventArgs) 方法

定義

引發 UploadProgressChanged 事件。

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

參數

範例

下列程式碼範例示範這個方法的實作,這個方法可由衍生自 WebClient 的類別自訂。

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

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

    base.OnUploadProgressChanged (e);

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

備註

繼承自這個類別的類別可以覆寫這個方法,以在事件發生時 UploadProgressChanged 執行其他工作。

引發事件會透過委派叫用此事件處理常式。 如需詳細資訊,請參閱 處理和引發事件

OnUploadProgressChanged 方法也允許衍生類別處理事件,而不用附加委派。 這是在衍生類別中處理事件的慣用技巧。

給繼承者的注意事項

OnUploadProgressChanged(UploadProgressChangedEventArgs) 衍生類別中覆寫時,請務必呼叫基類的 OnUploadProgressChanged(UploadProgressChangedEventArgs) 方法,讓已註冊的委派接收事件。

適用於