http://d.yimg.com/autoc.finance.yahoo.com/autoc?query=basf&callback=YAHOO.Finan_
  ce.SymbolSuggest.ssCallback

Imports System.Net
 
    Public Function Download(ByVal url As String) As IO.Stream
        Dim wr As HttpWebRequest = CType(HttpWebRequest.Create(url), _
          HttpWebRequest)
        wr.Method = "GET"
        wr.Timeout = 30000
        Using resp As HttpWebResponse = CType(wr.GetResponse(), HttpWebResponse)
            If resp.StatusCode = HttpStatusCode.OK Then
                Return resp.GetResponseStream()
            Else
                Return Nothing
            End If
        End Using
    End Function

    Private mGuiThread As Control = Me 'Die Form
    Private Delegate Sub AsyncCompletedDelegate(ByVal result As String)
 
    Public Sub DownloadAsync(ByVal url As String)
        Dim wr As HttpWebRequest = CType(WebRequest.Create(url), HttpWebRequest)
        wr.Method = "GET"
        wr.Timeout = 30000
        wr.BeginGetResponse(New AsyncCallback(AddressOf RequestComplete), wr)
    End Sub
    Private Sub RequestComplete(ByVal result As IAsyncResult)
        Try
            Dim request As HttpWebRequest = CType(result.AsyncState, _
              HttpWebRequest)
            Using resp As HttpWebResponse = CType(request.EndGetResponse( _
            result), HttpWebResponse)
                mGuiThread.Invoke(New AsyncCompletedDelegate(AddressOf _
                AsyncCompleted), StreamToStringAndClose(resp.GetResponseStream( _
                )))
            End Using
        Catch ex As Exception
            Debug.WriteLine("Fehler: " & ex.Message)
        End Try
    End Sub
    Private Sub AsyncCompleted(ByVal result As String)
        Debug.WriteLine("Result: " & result)
    End Sub

    Public Shared Function StreamToStringAndClose(ByVal stream As IO.Stream) As _
      String
        Dim res As String = String.Empty
        If stream IsNot Nothing Then
            If stream.CanRead Then
                Using sr As New IO.StreamReader(stream)
                    res = sr.ReadToEnd
                End Using
            End If
            CloseStream(stream)
        End If
        Return res
    End Function
    Public Shared Sub CloseStream(ByVal s As IO.Stream)
        If s IsNot Nothing Then
            s.Flush()
            s.Close()
            s.Dispose()
        End If
    End Sub