Visual Lanjutan Praktek Kasus 5(OPERATOR)

Public Class teori4
    Public hargasatuan, jumlahbeli, uangbayar, totalharga, uangkembali As Integer

    Private Sub teori4(ByVal sender As System.Object, ByVal e As System.EventArgs)
        ComboBox1.Items.Add("Pcs")
        ComboBox1.Items.Add("Set")
        ComboBox1.Items.Add("Box")
    End Sub

    Private Sub TextBox4_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs)
        If Not ((e.KeyChar >= "0" And e.KeyChar <= "9") Or e.KeyChar = vbBack) Then e.Handled = True
        If e.KeyChar = Chr(13) Then
            hargasatuan = TextBox3.Text
            jumlahbeli = TextBox4.Text
            totalharga = hargasatuan * jumlahbeli
            TextBox5.Text = totalharga
            TextBox5.Focus()
        End If
    End Sub

    Private Sub TextBox6_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox6.KeyPress
        If Not ((e.KeyChar >= "0" And e.KeyChar <= "9") Or e.KeyChar = vbBack) Then e.Handled = True
        If e.KeyChar = Chr(13) Then
            totalharga = TextBox5.Text
            uangbayar = TextBox6.Text
            uangkembali = uangbayar - totalharga
            TextBox7.Text = uangkembali
        End If
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        TextBox1.Clear()
        TextBox2.Clear()
        TextBox3.Clear()
        TextBox4.Clear()
        TextBox5.Clear()
        TextBox6.Clear()
        TextBox7.Clear()
        ComboBox1.SelectedIndex = -1
    End Sub

    Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
        If Not (Asc(e.KeyChar) = 8) Then
            Dim allowedChars As String = "abcdefghijklmnopqrstuvwxyz"
            If Not allowedChars.Contains(e.KeyChar.ToString.ToLower) Then
                e.KeyChar = ChrW(0)
                e.Handled = True
            End If
        End If
    End Sub

    Private Sub TextBox3_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox3.KeyPress
        If Not ((e.KeyChar >= "0" And e.KeyChar <= "9") Or e.KeyChar = vbBack) Then e.Handled = True
    End Sub

    Private Sub TextBox5_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox5.KeyPress
        If Not ((e.KeyChar >= "0" And e.KeyChar <= "9") Or e.KeyChar = vbBack) Then e.Handled = True
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        Dim pesan As String
        pesan = MsgBox("Are you sure want to exit ?", vbYesNo, "konfirmasi")
        If pesan = vbYes Then
        End If
    End Sub

    Private Sub teori4Closing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
        Dim pesan As String
        pesan = MsgBox("Are you sure want to exit ?", vbYesNo, "konfirmasi")
        If pesan = vbNo Then
            e.Cancel = True
        End If
    End Sub

    Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged

    End Sub
End Class