Change bank amount in word vb.net widow application

Form1.vb

Public Class BankAmountInWord

    Private Sub ButtonShow_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonShow.Click

        Dim amount, dummy, rev, rem1 As Integer

        rev = 0

        amount = CInt(TextBoxNumber.Text)

        If (amount > 99999) Then

            MessageBox.Show("Invalid Amount", "Invalid Amount")

        End If

        dummy = amount

        While (dummy <> 0)

            rev = rev * 10 + dummy Mod 10

            dummy = dummy \ 10

        End While

        MessageBox.Show("Amount In Word")

        While (rev <> 0)

            rem1 = rev Mod 10

            Select Case (rem1)

                Case 0

                    TextBoxWord.Text += "Zero"

                Case 1

                    TextBoxWord.Text += "One"

                Case 2

                    TextBoxWord.Text += "Two"

                Case 3

                    TextBoxWord.Text += "Three"

                Case 4

                    TextBoxWord.Text += "Four"

                Case 5

                    TextBoxWord.Text += "Five"

                Case 6

                    TextBoxWord.Text += "Six"

                Case 7

                    TextBoxWord.Text += "Seven"

                Case 8

                    TextBoxWord.Text += "Eight"

                Case 9

                    TextBoxWord.Text += "Nine"

            End Select

            rev = rev \ 10

        End While

        Dim den() As Integer = {1000, 500, 100, 50, 20, 10, 1}

        Dim i, tot As Integer

        i = 0

        tot = 0

        MessageBox.Show("DEMONSTRATIOON", "DEMONSTRATIOON")

        While (amount <> 0)

            rev = amount \ den(i)

            If (rev <> 0) Then

                MessageBox.Show(den(i) & " X " & rev & " = " & rev * den(i), "Amount Detailed")

                tot = tot + rev

            End If

            amount = amount Mod den(i)

            i = i + 1

        End While

        MessageBox.Show("Total Number of Notes: " & tot, "Total")

    End Sub

End Class

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