[CODE] Dim testohtml As String
    Dim righe As Integer = 0
    Dim textS As String

    Private Sub RichiestaWEB()
        'Crea una richiesta per un link
        Dim httprequest As WebRequest = HttpWebRequest.Create("http://javapc.poste.it/trackingPacchi")
        'Se richiesta dal server setta i credenziali d'accesso e post dei dati
        httprequest.Credentials = CredentialCache.DefaultCredentials
        httprequest.Method = "POST"
        httprequest.ContentType = "application/x-www-form-urlencoded"
        Dim encoding As New System.Text.ASCIIEncoding
        Dim postData As String = "Action=ActionTracking&Method=Tracking&SessionID=-1&ldv=" & Me.TextBox1.Text
        '
        'INIZIO PARTE DA CAPIRE...
        '
        Dim arByte As Byte() = encoding.GetBytes(postData)
        httprequest.ContentLength = arByte.Length
        Dim newStream As IO.Stream = httprequest.GetRequestStream
        newStream.Write(arByte, 0, arByte.Length)
        newStream.Close()
        '
        'FINE PARTE DA CAPIRE
        '
        'Prendi la risposta
        Dim risposta As HttpWebResponse = CType(httprequest.GetResponse(), HttpWebResponse)
        'Prendi lo stream contenente gli oggetti mandati dal server
        Dim datastream As Stream = risposta.GetResponseStream
        'Apri un stream usando uno StreamReader for facilità d'accesso
        Dim lettura As New StreamReader(datastream)
        'Leggi il contenuto
        Dim letturahtml As String = lettura.ReadToEnd
        'Chiudi gli stream lettura, datastream, risposta
        lettura.Close()
        datastream.Close()
        risposta.Close()

        testohtml = letturahtml
        Dim numerolinea1 As Integer
        Dim numerolinea2 As Integer
        Dim numerofine As Integer
        Dim iniziotable As String = "<table border=""0"" cellspacing=""2"" cellpadding=""3"" width=""100%"">"
        Dim finetable As String = "<BR>"
        numerolinea1 = InStr(testohtml, iniziotable)
        testohtml = testohtml.Remove(1, numerolinea1 - 1)
        numerolinea2 = InStr(testohtml, finetable)
        numerofine = testohtml.Length.ToString - numerolinea2
        testohtml = testohtml.Remove(numerolinea2 - 1, numerofine)

        Dim rtab As String = "<tr bgcolor=""#e8f404"">"
        Dim posizione As Integer = 0

Numero_righe_tabelle:
        posizione = testohtml.IndexOf(rtab, posizione)
        If posizione <> -1 Then
            righe += 1
            posizione += rtab.Length
            GoTo Numero_righe_tabelle
        End If
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        RichiestaWEB()
        textS = Nothing
        textS = testohtml
        Dim charconsiderato As Integer
        Dim parteriga1 As String = "<tr bgcolor=""#e8f404""><td><font size=1><b>"
        Dim parteriga2 As String = "</b></font></td><td><font size=1><b>"
        Dim parteriga3 As String = "</b></font></td></tr>"
        Dim parteriga4 As String = "  .FINE RIGA " & righe
        charconsiderato = InStr(textS, parteriga1)
        textS = textS.Remove(0, charconsiderato - 1)
        Dim i As Integer = 0
        For i = 0 To righe - 1
            charconsiderato = InStr(textS, parteriga1)
            textS = textS.Insert(charconsiderato - 1 + 42, "INIZIO RIGA" & i + 1 & " $1$")
            textS = textS.Remove(charconsiderato - 1, 42)
            charconsiderato = InStr(textS, parteriga2)
            textS = textS.Insert(charconsiderato - 1, "$2$")
            textS = textS.Remove(charconsiderato + 2, 36)
            charconsiderato = InStr(textS, parteriga2)
            textS = textS.Insert(charconsiderato - 1, "$3$")
            textS = textS.Remove(charconsiderato + 2, 36)
            charconsiderato = InStr(textS, parteriga3)
            textS = textS.Remove(charconsiderato - 1, 21)
            textS = textS.Insert(charconsiderato - 1, "  .FINE RIGA " & i + 1)
        Next
        charconsiderato = InStr(textS, parteriga4)
        Dim uno As Integer = charconsiderato + parteriga4.Length
        Dim due As Integer = textS.Length - uno
        textS = textS.Remove(uno - 1, due - 1)
        RichTextBox1.Text = textS[/CODE]