DownloadDataCompletedEventArgs Class

// Sample call : DownLoadDataInBackground ("http://www.contoso.com/GameScores.html");
void DownloadDataInBackground (String* address)
{
    System::Threading::AutoResetEvent* waiter = new System::Threading::AutoResetEvent (false);
    WebClient* client = new WebClient ();

    // Specify that the DownloadDataCallback method gets called
    // when the download completes.
    client->DownloadDataCompleted += new DownloadDataCompletedEventHandler (DownloadDataCallback);
    client->DownloadDataAsync (address, waiter);

    // Block the main application thread. Real applications
    // can perform other tasks while waiting for the download to complete.
    waiter->WaitOne ();
}

void DownloadDataCallback (Object* /*sender*/, DownloadDataCompletedEventArgs* e)
{
    System::Threading::AutoResetEvent* waiter = dynamic_cast<System::Threading::AutoResetEvent*>(e->UserToken);

    try
    {
        // If the request was not canceled and did not throw
        // an exception, display the resource.
        if (!e->Cancelled && e->Error == 0)
        {
            Byte data[] = dynamic_cast<Byte[]>(e->Result);
            String* textData = System::Text::Encoding::UTF8->GetString (data);

            Console::WriteLine (textData);
        }
    }
    __finally
    {
        // Let the main application thread resume.
        waiter->Set ();
    }
}