WebClient.OpenReadCompleted Händelse

public:
 event System::Net::OpenReadCompletedEventHandler ^ OpenReadCompleted;

public event System.Net.OpenReadCompletedEventHandler OpenReadCompleted;

member this.OpenReadCompleted : System.Net.OpenReadCompletedEventHandler 

Public Custom Event OpenReadCompleted As OpenReadCompletedEventHandler 

Public Event OpenReadCompleted As OpenReadCompletedEventHandler 

Händelsetyp

Exempel

I följande kodexempel visas hur du anger en händelsehanterare för den här händelsen.

void OpenResourceForReading2( String^ address )
{
   WebClient^ client = gcnew WebClient;
   Uri ^uri = gcnew Uri(address);

   client->OpenReadCompleted += gcnew OpenReadCompletedEventHandler( OpenReadCallback2 );
   client->OpenReadAsync( uri );
}

public static void OpenResourceForReading2(string address)
{
    WebClient client = new WebClient();
    Uri uri = new Uri(address);

    client.OpenReadCompleted += new OpenReadCompletedEventHandler(OpenReadCallback2);
    client.OpenReadAsync(uri);
}

Public Shared Sub OpenResourceForReading2(ByVal address As String)

    Dim client As WebClient = New WebClient()
    AddHandler client.OpenReadCompleted, AddressOf OpenReadCallback2
                Dim uri as Uri = New Uri(address)
    client.OpenReadAsync(uri)
End Sub

I följande kodexempel visas en implementering av en hanterare för den här händelsen.

void OpenReadCallback2( Object^ /*sender*/, OpenReadCompletedEventArgs^ e )
{
   Stream^ reply = nullptr;
   StreamReader^ s = nullptr;
   try
   {
      reply = dynamic_cast<Stream^>(e->Result);
      s = gcnew StreamReader( reply );
      Console::WriteLine( s->ReadToEnd() );
   }
   finally
   {
      if ( s != nullptr )
      {
         s->Close();
      }
      if ( reply != nullptr )
      {
         reply->Close();
      }
   }

}

private static void OpenReadCallback2(Object sender, OpenReadCompletedEventArgs e)
{
    Stream reply = null;
    StreamReader s = null;

    try
    {
        reply = (Stream)e.Result;
        s = new StreamReader(reply);
        Console.WriteLine(s.ReadToEnd());
    }
    finally
    {
        if (s != null)
        {
            s.Close();
        }

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

Private Shared Sub OpenReadCallback2(ByVal sender As Object, ByVal e As OpenReadCompletedEventArgs)

    Dim reply As Stream = Nothing
    Dim s As StreamReader = Nothing

    Try

        reply = CType(e.Result, Stream)
        s = New StreamReader(reply)
        Console.WriteLine(s.ReadToEnd())
    Finally

        If Not s Is Nothing Then

            s.Close()
        End If

        If Not reply Is Nothing Then

            reply.Close()
        End If
    End Try
End Sub

Kommentarer

Den här händelsen utlöses varje gång en asynkron åtgärd öppnas för att öppna en ström som innehåller en resurs slutförd. Dessa åtgärder startas genom att anropa OpenReadAsync metoderna.

OpenReadCompletedEventHandler är ombudet för den här händelsen. Klassen OpenReadCompletedEventArgs ger händelsehanteraren händelsedata.

Mer information om hur du hanterar händelser finns i Hantera och höja händelser.