Dim Alphabet As String = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
  Dim Zähler As Integer = 0
 
  Private Sub HauptForm_Load(sender As Object, e As EventArgs) Handles _
    MyBase.Load
    Alphabet = Alphabet.Reverse.ToArray 'Umkehren
  End Sub
 
  Private Sub TextBox1_KeyDown(sender As Object, e As KeyEventArgs) Handles _
    TextBox1.KeyDown
    If e.KeyCode = Keys.Enter Then
      e.SuppressKeyPress = True 'kein Beep
    End If
  End Sub
 
  Private Sub TextBox1_KeyUp(sender As Object, e As KeyEventArgs) Handles _
    TextBox1.KeyUp
    Dim tb = DirectCast(sender, TextBox)
    If e.KeyCode = Keys.Enter Then
      If tb.Text = Alphabet(Zähler) Then
        Label1.Text = "Richtig"
        Zähler += 1
      Else
        Label1.Text = "Bitte nochmal"
      End If
      tb.Clear()
    End If
  End Sub