WebClient.OnUploadProgressChanged(UploadProgressChangedEventArgs) 方法

定义

引发 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)

参数

示例

下面的代码示例演示此方法的实现,该方法可由派生自 WebClient的类进行自定义。

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...
}

注解

从此类继承的类可以重写此方法,以在事件发生时 UploadProgressChanged 执行其他任务。

引发事件时,将通过委托调用事件处理程序。 有关详细信息,请参阅 处理和引发事件

OnUploadProgressChanged 方法还允许派生类对事件进行处理而不必附加委托。 这是在派生类中处理事件的首选技术。

继承者说明

在派生类中重写 OnUploadProgressChanged(UploadProgressChangedEventArgs) 时,请务必调用基类的 OnUploadProgressChanged(UploadProgressChangedEventArgs) 方法,以便注册的委托接收 事件。

适用于