Kriptografi Caesar (Enkripsi kata)

Public Class Form1

    Private Sub Btnenkripsi_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Btnenkripsi.Click
        chiper.Text = ""
        Dim x As String
        Dim bil As Integer
        For i = 1 To Len(plain.Text)
            x = Microsoft.VisualBasic.Mid(plain.Text, i, 1)
            bil = Asc(x)
            bil = bil + 3
            x = Chr(bil)
            chiper.Text = chiper.Text & x
        Next i
    End Sub

    Private Sub BTNHAPUS_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BTNHAPUS.Click
        plain.Text = ""
        chiper.Text = ""
        dekripsi.Text = ""
    End Sub

    Private Sub BTNKELUAR_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BTNKELUAR.Click
        End
    End Sub

    Private Sub btndekripsi_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btndekripsi.Click
        dekripsi.Text = ""
        Dim x As String
        Dim bil As Integer
        For i = 1 To Len(chiper.Text)
            x = Microsoft.VisualBasic.Mid(chiper.Text, i, 1)
            bil = Asc(x)
            bil = bil - 3
            x = Chr(bil)
            dekripsi.Text = dekripsi.Text & x
        Next i
    End Sub
End Class