.NET Framework 4.6 and 4.5
Assembly: System (in System.dll)
'Declaration Public Delegate Sub OpenWriteCompletedEventHandler ( _ sender As Object, _ e As OpenWriteCompletedEventArgs _ )
The following code example demonstrates opening a stream to write data to be uploaded.
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
The following method is called when the stream is available.
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