Imports System.IO
Imports System.Runtime.Serialization.Formatters.Binary

  Dim hTable As New Collections.Hashtable
  Dim dicEntry As DictionaryEntry
  Dim sFilePath As String = Path.Combine( _
        Application.UserAppDataPath, "SerialHash.dat")

  Private Sub Button1_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles Button1.Click

    Try
      Dim stream As New FileStream(sFilePath, FileMode.Create, _
            FileAccess.Write, FileShare.Write)
      Dim converter As New BinaryFormatter
      converter.Serialize(stream, hTable)
      stream.Close()
    Catch ex As Exception
      MessageBox.Show(ex.Message)
    End Try
  End Sub

  Private Sub Button2_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles Button2.Click

    Try
      Dim stream As New FileStream(sFilePath, FileMode.Open, _
            FileAccess.Read)
      Dim converter As New BinaryFormatter
      hTable = CType(converter.Deserialize(stream), Hashtable)
      stream.Close()
    Catch ex As Exception
      MessageBox.Show(ex.Message)
    End Try

    ListAll()
  End Sub

  Private Sub Button3_Click(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles Button3.Click

    TextBox1.Text = (hTable.Count + 1).ToString

    If TextBox2.Text = String.Empty Then
      MessageBox.Show("Geben Sie einen Wert ein!", _
           "Keine Eingabe!", MessageBoxButtons.OK, _
           MessageBoxIcon.Exclamation)
      Exit Sub
    End If

    hTable.Add(TextBox1.Text, TextBox2.Text)
    ListAll()
  End Sub