Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
  System.EventArgs) Handles Button1.Click
        Dim iStream As Stream
        Dim sBuffer As String
 
        Dim fileDialog As New OpenFileDialog
 
        TextBox1.Text = ""
 
        fileDialog.InitialDirectory = "C:\"
        fileDialog.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
        fileDialog.FilterIndex = 2
        fileDialog.RestoreDirectory = True
 
        If fileDialog.ShowDialog() = DialogResult.OK Then
            iStream = fileDialog.OpenFile()
        End If
 
        If Not iStream Is Nothing Then
            Dim sr As New StreamReader(iStream)
            ' Datei auslesen und in TextBox anzeigen 
            sBuffer = sr.ReadToEnd()
            TextBox1.Text = sBuffer
            sr.Close()
        Else
            MsgBox("File Read Failed", MsgBoxStyle.Exclamation, "File" & _
              "Read/Write")
        End If
    End Sub
 
    Private Sub button2_Click(ByVal sender As Object, ByVal ByValue As _
      System.EventArgs) Handles Button2.Click
 
        Dim oStream As Stream
        Dim fileDialog As New SaveFileDialog
 
        fileDialog.InitialDirectory = "C:\"
        fileDialog.Filter = "txt files (*.txt)|*.txt|All files (*.*)|*.*"
        fileDialog.FilterIndex = 2
        fileDialog.RestoreDirectory = True
 
        If fileDialog.ShowDialog() = DialogResult.OK Then
            oStream = fileDialog.OpenFile()
        End If
        If Not oStream Is Nothing Then
            Dim sw As New StreamWriter(oStream)
            sw.Write(TextBox1.Text)
            sw.Close()
        Else
            MsgBox("File Save Failed", MsgBoxStyle.Exclamation, "File" & _
              "Read/Write")
        End If
    End Sub