WebClient.OnDownloadStringCompleted(DownloadStringCompletedEventArgs) 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
引發 DownloadStringCompleted 事件。
protected:
virtual void OnDownloadStringCompleted(System::Net::DownloadStringCompletedEventArgs ^ e);
protected virtual void OnDownloadStringCompleted (System.Net.DownloadStringCompletedEventArgs e);
abstract member OnDownloadStringCompleted : System.Net.DownloadStringCompletedEventArgs -> unit
override this.OnDownloadStringCompleted : System.Net.DownloadStringCompletedEventArgs -> unit
Protected Overridable Sub OnDownloadStringCompleted (e As DownloadStringCompletedEventArgs)
參數
範例
下列程式代碼範例示範這個方法的實作,這個方法可由衍生自 WebClient的類別自定義。
virtual void OnDownloadStringCompleted( DownloadStringCompletedEventArgs ^ e ) override
{
// Here you can perform any custom actions before the event is raised
// and event handlers are called...
WebClient::OnDownloadStringCompleted( e );
// Here you can perform any post event actions...
}
protected override void OnDownloadStringCompleted (DownloadStringCompletedEventArgs e)
{
// Here you can perform any custom actions before the event is raised
// and event handlers are called...
base.OnDownloadStringCompleted (e);
// Here you can perform any post event actions...
}
備註
謹慎
WebRequest
、HttpWebRequest
、ServicePoint
和 WebClient
已經過時,您不應該將它們用於新的開發。 請改用 HttpClient。
繼承自這個類別的類別可以覆寫此方法,以在發生 DownloadStringCompleted 事件時執行其他工作。
引發事件會透過委派叫用事件處理程式。 如需詳細資訊,請參閱 處理和引發事件。
OnDownloadStringCompleted 方法也允許衍生類別處理事件,而不附加委派。 這是在衍生類別中處理事件的慣用技術。
給繼承者的注意事項
在衍生類別中覆寫 OnDownloadStringCompleted(DownloadStringCompletedEventArgs) 時,請務必呼叫基類的 OnDownloadStringCompleted(DownloadStringCompletedEventArgs) 方法,讓已註冊的委派接收事件。