Dim alfabeto As New ArrayList()

    Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        Dim myChars() As String = {"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"}

        alfabeto.AddRange(myChars)

    End Sub

    Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress

        Dim myChar As Char = e.KeyChar
        For i As Integer = 0 To alfabeto.Count - 1
            If myChar = alfabeto.Item(i).ToString Then
                TextBox2.Text += alfabeto.Item((alfabeto.Count - 1) - i).ToString
            End If
        Next

    End Sub