Private Function DoUrlEncodeRequest() As String
        Dim enc As System.Text.Encoding = System.Text.Encoding.Default
        AddVal("val1", "üöäßÜÖÄ", enc)
        AddVal("val2", "abcdef", enc)
        Return UrlEncodePostRequest( _
          "http://localhost/ReceiveStrings/webform1.aspx", requestString, enc)
    End Function
 
    Private requestString As String = ""
 
    Private Sub AddVal(ByVal name As String, ByVal value As String, ByVal enc _
      As System.Text.Encoding)
        If requestString <> "" Then
            requestString += "&"
        End If
        requestString += name & "=" & System.Web.HttpUtility.UrlEncode(value, _
          enc)
    End Sub
 
    Private Function UrlEncodePostRequest(ByVal url As String, ByVal data As _
      String, ByVal enc As System.Text.Encoding) As String
        Dim req As HttpWebRequest = CType(WebRequest.Create(url), _
        HttpWebRequest)
        req.Method = "POST"
        Dim bdata() As Byte = enc.GetBytes(data)
        req.ContentType = "application/x-www-form-urlencoded; charset=" & _
          enc.WebName
        req.ContentLength = bdata.Length
        req.KeepAlive = False
        Dim out As Stream = req.GetRequestStream()
        out.Write(bdata, 0, bdata.Length)
        out.Close()
        Dim resp As WebResponse = req.GetResponse()
        Dim sr As New StreamReader(resp.GetResponseStream(), enc)
        Dim res As String = sr.ReadToEnd()
        sr.Close()
        resp.Close()
        Return res
    End Function

 
    Public retVal As String
    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        'Put user code to initialize the page here
        System.Diagnostics.Debug.WriteLine(Request.ContentEncoding)
        System.Diagnostics.Debug.WriteLine(New System.IO.StreamReader( _
          Request.InputStream, Request.ContentEncoding).ReadToEnd)
        System.Diagnostics.Debug.WriteLine(Request.Item("val1"))
        System.Diagnostics.Debug.WriteLine(Request.Item("val2"))
        Response.ContentEncoding = Request.ContentEncoding
        retVal = "val1= " & Request.Item("val1") & " val2=" & Request.Item( _
          "val2")
    End Sub

________
Alle Angaben ohne Gewähr. Keine Haftung für Vorschläge, Tipps oder sonstige Hilfe, falls es schiefgeht, nur Zeit verschwendet oder man sonst nicht zufrieden ist