UploadFileCompletedEventHandler UploadFileCompletedEventHandler UploadFileCompletedEventHandler UploadFileCompletedEventHandler Delegate

Definizione

Rappresenta il metodo che gestirà l'evento UploadFileCompleted di un oggetto WebClient.Represents the method that will handle the UploadFileCompleted event of a WebClient.

public delegate void UploadFileCompletedEventHandler(System::Object ^ sender, UploadFileCompletedEventArgs ^ e);
public delegate void UploadFileCompletedEventHandler(object sender, UploadFileCompletedEventArgs e);
type UploadFileCompletedEventHandler = delegate of obj * UploadFileCompletedEventArgs -> unit
Public Delegate Sub UploadFileCompletedEventHandler(sender As Object, e As UploadFileCompletedEventArgs)

Parametri

sender
Object Object Object Object

Origine dell'evento.The source of the event.

Ereditarietà
UploadFileCompletedEventHandlerUploadFileCompletedEventHandlerUploadFileCompletedEventHandlerUploadFileCompletedEventHandler

Esempi

Nell'esempio di codice seguente viene illustrato il caricamento asincrono di un file.The following code example demonstrates asynchronously uploading a file.

// Sample call: UploadFileInBackground("http://www.contoso.com/fileUpload.aspx", "data.txt")
void UploadFileInBackground( String^ address, String^ fileName )
{
   System::Threading::AutoResetEvent^ waiter = gcnew System::Threading::AutoResetEvent( false );
   WebClient^ client = gcnew WebClient;
   Uri ^uri = gcnew Uri(address);
   String^ method = "POST";
   
   // Specify that that UploadFileCallback method gets called
   // when the file upload completes.
   client->UploadFileCompleted += gcnew UploadFileCompletedEventHandler( UploadFileCallback );
   client->UploadFileAsync( uri, method, fileName, waiter );
   
   // Block the main application thread. Real applications
   // can perform other tasks while waiting for the upload to complete.
   waiter->WaitOne();
   Console::WriteLine( "File upload is complete." );
}


// Sample call: UploadFileInBackground("http://www.contoso.com/fileUpload.aspx", "data.txt")
public static void UploadFileInBackground (string address, string fileName)
{
    System.Threading.AutoResetEvent waiter = new System.Threading.AutoResetEvent (false);
    WebClient client = new WebClient ();
    Uri uri = new Uri(address);
    string method = "POST";

    // Specify that that UploadFileCallback method gets called
    // when the file upload completes.
    client.UploadFileCompleted += new UploadFileCompletedEventHandler (UploadFileCallback);
    client.UploadFileAsync (uri, method, fileName, waiter);

    // Block the main application thread. Real applications
    // can perform other tasks while waiting for the upload to complete.
    waiter.WaitOne ();
    Console.WriteLine ("File upload is complete.");
}

'  Sample call: UploadFileInBackground("http:' www.contoso.com/fileUpload.aspx", "data.txt")
Public Shared Sub UploadFileInBackground(ByVal address As String, ByVal fileName As String)

	Dim waiter As System.Threading.AutoResetEvent = New System.Threading.AutoResetEvent(False)
	Dim client As WebClient = New WebClient()
	Dim method As String = "POST"
                       Dim uri as Uri =  New Uri(address)

	'  Specify that that UploadFileCallback method gets called
	'  when the file upload completes.
	AddHandler client.UploadFileCompleted, AddressOf UploadFileCallback
	client.UploadFileAsync(uri, method, fileName, waiter)

	'  Block the main application thread. Real applications
	'  can perform other tasks while waiting for the upload to complete.
	waiter.WaitOne()
	Console.WriteLine("File upload is complete.")
End Sub

Il metodo seguente viene chiamato al termine del caricamento.The following method is called when the upload completes.

void UploadFileCallback( Object^ /*sender*/, UploadFileCompletedEventArgs^ e )
{
   System::Threading::AutoResetEvent^ waiter = dynamic_cast<System::Threading::AutoResetEvent^>(e->UserState);
   ;
   try
   {
      String^ reply = System::Text::Encoding::UTF8->GetString( e->Result );
      Console::WriteLine( reply );
   }
   finally
   {
      
      // If this thread throws an exception, make sure that
      // you let the main application thread resume.
      waiter->Set();
   }

}


private static void UploadFileCallback (Object sender, UploadFileCompletedEventArgs e)
{
    System.Threading.AutoResetEvent waiter = (System.Threading.AutoResetEvent)e.UserState;;
    try
    {
        string reply = System.Text.Encoding.UTF8.GetString (e.Result);

        Console.WriteLine (reply);
    }
    finally
    {
        // If this thread throws an exception, make sure that
        // you let the main application thread resume.
        waiter.Set ();
    }
}

Private Shared Sub UploadFileCallback(ByVal sender As Object, ByVal e As System.Net.UploadFileCompletedEventArgs)

    Dim waiter As System.Threading.AutoResetEvent = CType(e.UserState, System.Threading.AutoResetEvent)
    Try

        Dim reply As String = System.Text.Encoding.UTF8.GetString(e.Result)
        Console.WriteLine(reply)
    Finally
        '  If this thread throws an exception, make sure that
        '  you let the main application thread resume.
        waiter.Set()
    End Try
End Sub

Commenti

Quando si crea un delegato UploadFileCompletedEventHandler, si identifica il metodo che gestirà l'evento.When you create a UploadFileCompletedEventHandler delegate, you identify the method that will handle the event. Per associare l'evento al gestore eventi in uso, aggiungere all'evento un'istanza del delegato.To associate the event with your event handler, add an instance of the delegate to the event. Il gestore eventi viene chiamato ogni volta che si verifica l'evento, a meno che non venga rimosso il delegato.The event handler is called whenever the event occurs, unless you remove the delegate. Per ulteriori informazioni sui delegati del gestore eventi, vedere gestione e generazione di eventi.For more information about event handler delegates, see Handling and Raising Events.

Metodi di estensione

GetMethodInfo(Delegate) GetMethodInfo(Delegate) GetMethodInfo(Delegate) GetMethodInfo(Delegate)

Ottiene un oggetto che rappresenta il metodo rappresentato dal delegato specificato.Gets an object that represents the method represented by the specified delegate.

Si applica a