Tutorial Program Kalkulator

TUTORIAL

PROGRAM APLIKASI KALKULATOR

1. Deskripsi

Program yang kami buat ini adalah program kalkulator yang dapat digunakan untuk menghitung penghitungan aritmatika sederhana.

2. Tujuan dan Manfaat

Tujuan dari program ini adalah pengaplikasian ilmu dari praktikum yang diberikan oleh asistan-asistan dan mengetahui penghitungan aritmatika.

3. Sasaran

Pelajar pendidikan yang ingin menggunakan kalkulator sebagai alat penghitung aritmatika.

Langkah-Langkahnya :

1.      Bukalah program Visual Basic 2010 pada komputer Anda.

2.      Isilah Setiap Form dan Listingnya seperti yang dibawah ini.

No	Komponen	Properties	keterangan
1	Form1	Name	Form1
		Text	Kalkulator
		Background	WindowsApplication1.My.Resources.Resources.a
		Display	CentertoScreen
2	TextBox1	Name	TextBox1
		Text
3	TextBox2	Name	TextBox2
		Text
4	Button1	Name	Button1
		Text	1
5	Button2	Name	Button2
		Text	2
6	Button3	Name	Button3
		Text	3
7	Button4	Name	Button4
		Text	4
8	Button5	Name	Button5
		Text	5
9	Button6	Name	Button6
		Text	6
10	Button7	Name	Button7
		Text	7
11	Button8	Name	Button8
		Text	8
12	Button9	Name	Button9
		Text	9
13	Button10	Name	Button10
		Text	0
14	Button11	Name	Button11
		Text	.
15	Button12	Name	Button12
		Text	Sin
16	Button13	Name	Button13
		Text	Cos
17	Button14	Name	Button14
		Text	Tan
18	Button15	Name	Button15
		Text	Log
19	Button16	Name	Button16
		Text	X
20	Button17	Name	Button17
		Text	/
21	Button18	Name	Button18
		Text	+
22	Button19	Name	Button19
		Text	-
23	Button20	Name	Button20
		Text	N!
24	Button21	Name	Button21
		Item	^
25	Button22	Name	Button22
		Text
26	Button23	Name	Button23
		Text	Mod
27	Button24	Name	Button24
		Text	Backspace
28	Button 25	Name	Button25
		Text	C
29	Button 26	Name	Button 26
		Text	Off
30	Button 27	Name	Button 27
		Text	On
31	Button 28	Name	Button 28
		Text	=
31	Button 29	Name	Button 29
		Text	Exit

Lalu masukkan listing berikut ini:

Public Class form1

    Dim Angka, Hasil As Double

    Dim proses As String

    Dim a, b As Integer

    Dim tombolON As Boolean

    Const pi As Double = 3.14159265358979

Untuk mendeklarasikan  variabel-variabel seperti tipe data di atas. Variabel angka dan hasil dalam tipe data double.

Variabel proses dalam tipe data string. Variabel a,b dalam tipe data integer.

    Private Sub form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        tombolON = False

        Me.ForeColor = Color.GhostWhite

        Button29.ForeColor = Color.Black

        Button30.ForeColor = Color.Black

    End Sub

Untuk menonaktifkan tombol On. Dan memberi warna pada button 29 dan 30.

    Private Sub Button7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button7.Click

        If tombolON = False Then

            Exit Sub

        End If

        If TextBox1.Text = "0" Then

            TextBox1.Text = "1"

            TextBox2.Text = "1"

        Else

            TextBox1.Text = TextBox1.Text & "1"

            TextBox2.Text = TextBox2.Text & "1"

        End If

    End Sub

Untuk memasukkan angka 1.

    Private Sub Button8_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button8.Click

        If tombolON = False Then

            Exit Sub

        End If

        If TextBox1.Text = "0" Then

            TextBox1.Text = "2"

            TextBox2.Text = "2"

        Else

            TextBox1.Text = TextBox1.Text & "2"

            TextBox2.Text = TextBox2.Text & "2"

        End If

    End Sub

Untuk memasukkan angka 2.

    Private Sub Button9_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button9.Click

        If tombolON = False Then

            Exit Sub

        End If

        If TextBox1.Text = "0" Then

            TextBox1.Text = "3"

            TextBox2.Text = "3"

        Else

            TextBox1.Text = TextBox1.Text & "3"

            TextBox2.Text = TextBox2.Text & "3"

        End If

    End Sub

Untuk memasukkan angka 3.

    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click

        If tombolON = False Then

            Exit Sub

        End If

        If TextBox1.Text = "0" Then

            TextBox1.Text = "4"

            TextBox2.Text = "4"

        Else

            TextBox1.Text = TextBox1.Text & "4"

            TextBox2.Text = TextBox2.Text & "4"

        End If

    End Sub

Untuk memasukkan angka 4.

    Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click

        If tombolON = False Then

            Exit Sub

        End If

        If TextBox1.Text = "0" Then

            TextBox1.Text = "5"

            TextBox2.Text = "5"

        Else

            TextBox1.Text = TextBox1.Text & "5"

            TextBox2.Text = TextBox2.Text & "5"

        End If

    End Sub

Untuk memasukkan angka 5.

    Private Sub Button6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button6.Click

        If tombolON = False Then

            Exit Sub

        End If

        If TextBox1.Text = "0" Then

            TextBox1.Text = "6"

            TextBox2.Text = "6"

        Else

            TextBox1.Text = TextBox1.Text & "6"

            TextBox2.Text = TextBox2.Text & "6"

        End If

    End Sub

Untuk memasukkan angka 6.

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        If tombolON = False Then

            Exit Sub

        End If

        If TextBox1.Text = "0" Then

            TextBox1.Text = "7"

            TextBox2.Text = "7"

        Else

            TextBox1.Text = TextBox1.Text & "7"

            TextBox2.Text = TextBox2.Text & "7"

        End If

    End Sub

Untuk memasukkan angka 7.

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

        If tombolON = False Then

            Exit Sub

        End If

        If TextBox1.Text = "0" Then

            TextBox1.Text = "8"

            TextBox2.Text = "8"

        Else

            TextBox1.Text = TextBox1.Text & "8"

            TextBox2.Text = TextBox2.Text & "8"

        End If

    End Sub

Untuk memasukkan angka 8.

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click

        If tombolON = False Then

            Exit Sub

        End If

        If TextBox1.Text = "0" Then

            TextBox1.Text = "9"

            TextBox2.Text = "9"

        Else

            TextBox1.Text = TextBox1.Text & "9"

            TextBox2.Text = TextBox2.Text & "9"

        End If

    End Sub

Untuk memasukkan angka 9.

    Private Sub Button10_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button10.Click

        If tombolON = False Then

            Exit Sub

        End If

        TextBox1.Text = TextBox1.Text & "."

        TextBox2.Text = TextBox2.Text & "."

    End Sub

    Private Sub Button11_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button11.Click

        If tombolON = False Then

            Exit Sub

        End If

        If TextBox1.Text = "0" Then

            TextBox1.Text = "0"

            TextBox2.Text = "0"

        Else

            TextBox1.Text = TextBox1.Text & "0"

            TextBox2.Text = TextBox2.Text & "0"

        End If

    End Sub

Untuk memasukkan angka 0.

    Private Sub Button12_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button12.Click

        TextBox2.Text = TextBox2.Text & "+"

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^1/2″"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

                Case "mod"

                    Call m()

            End Select

        Else

            Call Tambah()

        End If

        proses = "+"

        TextBox1.Text = ""

    End Sub

    Private Sub Tambah()

        If Angka = "0" Then

            Angka = Val(TextBox1.Text)

        Else

            Angka = Angka + Val(TextBox1.Text)

        End If

        proses = "+"

        TextBox1.Text = ""

    End Sub

Untuk mengoperasikan aritmatika penjumlahan, bisa dalam pararel juga. Di sini banyak kemungkinan setelah aritmatika penjumlahan, bisa disambung dengan aritmatika lain. Maksudnya case call tambah ini dibuktikan dengan listing Private sub tambah () ini.

    Private Sub Button13_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button13.Click

        TextBox2.Text = TextBox2.Text & "-"

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

                Case "mod"

                    Call m()

            End Select

        Else

            Call kurang()

        End If

        proses = "-"

        TextBox1.Text = ""

    End Sub

    Private Sub kurang()

        If Angka = "0" Then

            Angka = Val(TextBox1.Text)

        Else

            Angka = Angka - Val(TextBox1.Text)

        End If

        proses = "-"

        TextBox1.Text = ""

    End Sub

Untuk mengoperasikan aritmatika pengurangan, bisa dalam pararel juga. Di sini banyak kemungkinan setelah aritmatika penjumlahan, bisa disambung dengan aritmatika lain. Maksudnya case call kurang disini ini dibuktikan dengan listing Private sub kurang () ini.

    Private Sub Button14_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button14.Click

        TextBox2.Text = TextBox2.Text & "x"

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

                Case "mod"

                    Call m()

            End Select

        Else

            Call kali()

        End If

        proses = "x"

        TextBox1.Text = ""

    End Sub

    Private Sub kali()

        If Angka = "0" Then

            Angka = Val(TextBox1.Text)

        Else

            Angka = Angka * Val(TextBox1.Text)

        End If

        proses = "x"

        TextBox1.Text = ""

    End Sub

Untuk mengoperasikan aritmatika perkalian, bisa dalam pararel juga. Di sini banyak kemungkinan setelah aritmatika perkalian, bisa disambung dengan aritmatika lain. Maksudnya case call tambah ini dibuktikan dengan listing Private sub kali () ini.

    Private Sub Button15_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button15.Click

        TextBox2.Text = TextBox2.Text & "/"

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

                Case "mod"

                    Call m()

            End Select

        Else

            Call bagi()

        End If

        proses = "/"

        TextBox1.Text = 0

    End Sub

    Private Sub bagi()

        If Angka = "0" Then

            Angka = Val(TextBox1.Text)

        Else

            Angka = Angka / Val(TextBox1.Text)

        End If

        proses = "/"

        TextBox1.Text = ""

    End Sub

Untuk mengoperasikan aritmatika pembagian, bisa dalam pararel juga. Di sini banyak kemungkinan setelah aritmatika pembagian, bisa disambung dengan aritmatika lain. Maksudnya case call bagi ini dibuktikan dengan listing Private sub bagi () ini.

    Private Sub Button25_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button25.Click

        TextBox2.Text = TextBox2.Text & "mod"

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

                Case "mod"

                    Call m()

            End Select

        Else

            Call m()

        End If

    End Sub

    Private Sub m()

        Angka = Val(TextBox1.Text)

        If Angka = Val(TextBox1.Text) Then

        Else

            Angka = Angka Mod Val(TextBox1.Text)

        End If

        proses = "mod"

        TextBox1.Text = ""

    End Sub

Untuk mengoperasikan aritmatika mod. Mod ini untuk mencari sisa hasil bagi. Di sini banyak kemungkinan setelah aritmatika mod, bisa disambung dengan aritmatika lain. Maksudnya case call mod ini dibuktikan dengan listing Private sub mod () ini.

    Private Sub Button23_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button23.Click

        TextBox2.Text = TextBox2.Text & "!"

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

                Case "mod"

                    Call m()

            End Select

        Else

            Call faktorial()

        End If

        proses = "N!"

    End Sub

    Private Sub faktorial()

        a = 1

        For i = 1 To Val(TextBox1.Text)

            a = a * i

        Next

    End Sub

Untuk mengoperasikan aritmatika faktorial . Maksudnya case call faktorial ini dibuktikan dengan listing Private sub faktorial () ini.

    Private Sub Button17_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button17.Click

        TextBox2.Text = "Sin" & TextBox2.Text

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

                Case "mod"

                    Call m()

            End Select

        Else

            Call Sin()

        End If

        proses = "Sin"

        TextBox1.Text = ""

    End Sub

    Private Sub Sin()

        Angka = Val(TextBox1.Text)

        Angka = Math.Sin(Angka * (pi / 180))

        proses = "Sin"

        TextBox1.Text = ""

    End Sub

Untuk mengoperasikan aritmatika trigonometri sin ini. Maksudnya case call sin  ini dibuktikan dengan listing Private sub sin () ini.

    Private Sub Button19_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button19.Click

        TextBox2.Text = "Cos" & TextBox2.Text

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

                Case "mod"

                    Call m()

            End Select

        Else

            Call Cos()

        End If

        proses = "Cos"

    End Sub

    Private Sub Cos()

        Angka = Val(TextBox1.Text)

        Angka = Math.Cos(Angka * (pi / 180))

        proses = "Cos"

        TextBox1.Text = ""

    End Sub

Untuk mengoperasikan aritmatika trigonometri cos ini. Maksudnya case call sin  ini dibuktikan dengan listing Private sub cos () ini.

    Private Sub Button18_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button18.Click

        TextBox2.Text = TextBox2.Text & "Tan"

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

                Case "mod"

                    Call m()

            End Select

        Else

            Call Tan()

        End If

        proses = "Tan"

        TextBox1.Text = ""

    End Sub

    Private Sub Tan()

        Angka = Val(TextBox1.Text)

        Angka = Math.Tan(Angka * (pi / 180))

        proses = "Tan"

        TextBox1.Text = ""

    End Sub

Untuk mengoperasikan aritmatika trigonometri tan ini. Maksudnya case call sin  ini dibuktikan dengan listing Private sub tan () ini

    Private Sub Button21_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button21.Click

If TextBox1.Text.Length > 0 Then

            TextBox1.Text = TextBox1.Text.Remove(TextBox1.Text.Length - 1, 1)

        End If

        If TextBox2.Text.Length > 0 Then

            TextBox2.Text = TextBox2.Text.Remove(TextBox2.Text.Length - 1, 1)

        End If

    End Sub

 Ini untuk menegatifkan angka yang telah dimasukkan dalam textbox.

    Private Sub Button26_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button26.Click

        TextBox2.Text = ""

        TextBox1.Text = ""

    End Sub

Listing ini untuk menghapus angka yang telah dimasukkan.

    Private Sub Button20_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button20.Click

        If proses = "+" Then

            Hasil = Angka + Val(TextBox1.Text)

            TextBox1.Text = Hasil

        ElseIf proses = "-" Then

            Hasil = Angka - Val(TextBox1.Text)

            TextBox1.Text = Hasil

        ElseIf proses = "x" Then

            Hasil = Angka * Val(TextBox1.Text)

            TextBox1.Text = Hasil

        ElseIf proses = "/" Then

            Hasil = Angka / Val(TextBox1.Text)

            TextBox1.Text = Hasil

        ElseIf proses = "^" Then

            Hasil = Angka ^ Val(TextBox1.Text)

            TextBox1.Text = Hasil

        ElseIf proses = "√" Then

            Hasil = Val(TextBox1.Text) ^ 0.5

            TextBox1.Text = Hasil

        ElseIf proses = "Cos" Then

            Hasil = Math.Cos(Val(TextBox1.Text) * (pi / 180))

            TextBox1.Text = Hasil

        ElseIf proses = "Sin" Then

            Hasil = Math.Sin(Val(TextBox1.Text) * (pi / 180))

            TextBox1.Text = Hasil

        ElseIf proses = "Tan" Then

            Hasil = Math.Tan(Val(TextBox1.Text) * (pi / 180))

            TextBox1.Text = Hasil

        ElseIf proses = "N!" Then

            TextBox1.Text = Str(a)

        ElseIf proses = "log10" Then

            Hasil = Math.Log10(Val(TextBox1.Text))

            TextBox1.Text = Hasil

        ElseIf proses = "mod" Then

            Hasil = Angka Mod Val(TextBox1.Text)

            TextBox1.Text = Hasil

        End If

        proses = ""

        Angka = 0

    End Sub

Untuk  sama dengan

    Private Sub Button16_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button16.Click

        TextBox2.Text = "√" & TextBox2.Text

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

            End Select

        Else

            Call akar()

        End If

        proses = "√"

        TextBox1.Text = ""

    End Sub

    Private Sub akar()

        Angka = Val(TextBox1.Text)

        Angka = Angka ^ 0.5

        proses = "√"

        TextBox1.Text = ""

    End Sub

Untuk mengakar suatu bilangan yang telah diinput. Maksudnya case call akar ini dibuktikan dengan listing Private sub akar () ini.

    Private Sub Button27_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button27.Click

        TextBox2.Text = TextBox2.Text & "^"

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

            End Select

        Else

            Call pangkat()

        End If

        proses = "^"

        TextBox1.Text = ""

    End Sub

    Private Sub pangkat()

        If Angka = "0" Then

            Angka = Val(TextBox1.Text)

        Else

            Angka = Angka ^ Val(TextBox1.Text)

        End If

        proses = "^"

        TextBox1.Text = ""

    End Sub

Untuk pangkat suatu bilangan yang telah diinput. Maksudnya case call pangkat ini dibuktikan dengan listing Private sub pangkat () ini.

    Private Sub Button22_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button22.Click

        TextBox2.Text = TextBox2.Text & "log"

        If proses <> "" Then

            Select Case proses

                Case "+"

                    Call Tambah()

                Case "-"

                    Call kurang()

                Case "x"

                    Call kali()

                Case "/"

                    Call bagi()

                Case "^"

                    Call pangkat()

                Case "log"

                    Call Log()

                Case "^0.5"

                    Call akar()

                Case "N!"

                    Call faktorial()

                Case "Sin"

                    Call Sin()

                Case "Cos"

                    Call Cos()

                Case "Tan"

                    Call Tan()

            End Select

        Else

            Call Log()

        End If

        proses = "log10"

    End Sub

    Private Sub Log()

        Angka = Val(TextBox1.Text)

        Angka = Math.Log10(Angka)

        proses = "log10"

        TextBox1.Text = ""

    End Sub

Untuk menetukan log suatu bilangan yang telah diinput. Maksudnya case log akar ini dibuktikan dengan listing Private sub log () ini.

    Private Sub Button30_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button30.Click

        tombolON = True

        Me.ForeColor = Color.Black

    End Sub

    Private Sub Button29_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button29.Click

        tombolON = False

        Me.ForeColor = Color.GhostWhite

        Button29.ForeColor = Color.Black

    End Sub

    Private Sub Button28_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button28.Click

        Close()

    End Sub

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

    End Sub

End Class

 Dan tampilah akan jadi seperti ini.