OpenWriteCompletedEventArgs Classe

Definizione

Fornisce dati per l'evento OpenWriteCompleted.Provides data for the OpenWriteCompleted event.

public ref class OpenWriteCompletedEventArgs : System::ComponentModel::AsyncCompletedEventArgs
public class OpenWriteCompletedEventArgs : System.ComponentModel.AsyncCompletedEventArgs
type OpenWriteCompletedEventArgs = class
    inherit AsyncCompletedEventArgs
Public Class OpenWriteCompletedEventArgs
Inherits AsyncCompletedEventArgs
Ereditarietà
OpenWriteCompletedEventArgs

Esempi

Nell'esempio di codice seguente viene illustrata l'apertura di un flusso per la scrittura dei dati da caricare.The following code example demonstrates opening a stream to write data to be uploaded.

void OpenResourceForPosting( String^ address )
{
   WebClient^ client = gcnew WebClient;
   Uri ^uri = gcnew Uri(address);
   
   // Specify that the OpenWriteCallback method gets called
   // when the writeable stream is available.
   client->OpenWriteCompleted += gcnew OpenWriteCompletedEventHandler( OpenWriteCallback2 );
   client->OpenWriteAsync( uri );
   
   // Applications can perform other tasks
   // while waiting for the upload to complete.
}


public static void OpenResourceForPosting (string address)
{
    WebClient client = new WebClient ();
    Uri uri = new Uri(address);

    // Specify that the OpenWriteCallback method gets called
    // when the writeable stream is available.
    client.OpenWriteCompleted += new OpenWriteCompletedEventHandler (OpenWriteCallback2);
    client.OpenWriteAsync (uri);
    // Applications can perform other tasks
    // while waiting for the upload to complete.
}

Public Shared Sub OpenResourceForPosting(ByVal address As String)

    Dim client As WebClient = New WebClient()
    '  Specify that the OpenWriteCallback method gets called
    '  when the writeable stream is available.
    AddHandler client.OpenWriteCompleted, AddressOf OpenWriteCallback2
                Dim uri as Uri = New Uri(address)
    client.OpenWriteAsync(uri)
    '  Applications can perform other tasks
    '  while waiting for the upload to complete.
End Sub

Il metodo seguente viene chiamato quando il flusso è disponibile.The following method is called when the stream is available.

void OpenWriteCallback2( Object^ /*sender*/, OpenWriteCompletedEventArgs^ e )
{
   Stream^ body = nullptr;
   StreamWriter^ s = nullptr;
   try
   {
      body = dynamic_cast<Stream^>(e->Result);
      s = gcnew StreamWriter( body );
      s->AutoFlush = true;
      s->Write( "This is content data to be sent to the server." );
   }
   finally
   {
      if ( s != nullptr )
      {
         s->Close();
      }
      if ( body != nullptr )
      {
         body->Close();
      }
   }

}


private static void OpenWriteCallback2 (Object sender, OpenWriteCompletedEventArgs e)
{
    Stream body = null;
    StreamWriter s = null;

    try
    {
        body = (Stream)e.Result;
        s = new StreamWriter (body);
        s.AutoFlush = true;
        s.Write ("This is content data to be sent to the server.");
    }
    finally
    {
        if (s != null)
        {
            s.Close ();
        }

        if (body != null)
        {
            body.Close ();
        }
    }
}

Private Shared Sub OpenWriteCallback2(ByVal sender As Object, ByVal e As OpenWriteCompletedEventArgs)

    Dim body As Stream = Nothing
    Dim s As StreamWriter = Nothing

    Try

        body = CType(e.Result, Stream)
        s = New StreamWriter(body)
        s.AutoFlush = True
        s.Write("This is content data to be sent to the server.")
    Finally

        If Not s Is Nothing Then

            s.Close()
        End If

        If Not body Is Nothing Then

            body.Close()
        End If
    End Try
End Sub

Commenti

Le istanze di questa classe vengono passate OpenWriteCompletedEventHandler ai metodi.Instances of this class are passed to OpenWriteCompletedEventHandler methods.

Proprietà

Cancelled

Ottiene un valore che indica se un'operazione asincrona è stata annullata.Gets a value indicating whether an asynchronous operation has been canceled.

(Ereditato da AsyncCompletedEventArgs)
Error

Ottiene un valore che indica l'errore verificatosi durante un'operazione asincrona.Gets a value indicating which error occurred during an asynchronous operation.

(Ereditato da AsyncCompletedEventArgs)
Result

Ottiene un flusso di scrittura utilizzato per inviare dati al server.Gets a writable stream that is used to send data to a server.

UserState

Ottiene l’identificatore univoco per l'attività asincrona.Gets the unique identifier for the asynchronous task.

(Ereditato da AsyncCompletedEventArgs)

Metodi

Equals(Object)

Determina se l'oggetto specificato è uguale all'oggetto corrente.Determines whether the specified object is equal to the current object.

(Ereditato da Object)
GetHashCode()

Funge da funzione hash predefinita.Serves as the default hash function.

(Ereditato da Object)
GetType()

Ottiene l'oggetto Type dell'istanza corrente.Gets the Type of the current instance.

(Ereditato da Object)
MemberwiseClone()

Crea una copia superficiale dell'oggetto Object corrente.Creates a shallow copy of the current Object.

(Ereditato da Object)
RaiseExceptionIfNecessary()

Genera un'eccezione fornita dall'utente in caso di errore in un'operazione asincrona.Raises a user-supplied exception if an asynchronous operation failed.

(Ereditato da AsyncCompletedEventArgs)
ToString()

Restituisce una stringa che rappresenta l'oggetto corrente.Returns a string that represents the current object.

(Ereditato da Object)

Si applica a