Public Class Form1

    Public total1 As Integer

    Private Sub Btn0_Click(sender As Object, e As EventArgs) Handles Btn0.Click
        TextBox1.Text = TextBox1.Text & "0"
    End Sub

    Private Sub Btn1_Click(sender As Object, e As EventArgs) Handles Btn1.Click
        TextBox1.Text = TextBox1.Text & "1"
    End Sub

    Private Sub Btn2_Click(sender As Object, e As EventArgs) Handles Btn2.Click
        TextBox1.Text = TextBox1.Text & "2"
    End Sub

    Private Sub Btn3_Click(sender As Object, e As EventArgs) Handles Btn3.Click
        TextBox1.Text = TextBox1.Text & "3"
    End Sub

    Private Sub Btn4_Click(sender As Object, e As EventArgs) Handles Btn4.Click
        TextBox1.Text = TextBox1.Text & "4"
    End Sub

    Private Sub Btn5_Click(sender As Object, e As EventArgs) Handles Btn5.Click
        TextBox1.Text = TextBox1.Text & "5"
    End Sub

    Private Sub Btn6_Click(sender As Object, e As EventArgs) Handles Btn6.Click
        TextBox1.Text = TextBox1.Text & "6"
    End Sub

    Private Sub Btn7_Click(sender As Object, e As EventArgs) Handles Btn7.Click
        TextBox1.Text = TextBox1.Text & "7"
    End Sub

    Private Sub Btn8_Click(sender As Object, e As EventArgs) Handles Btn8.Click
        TextBox1.Text = TextBox1.Text & "8"
    End Sub

    Private Sub Btn9_Click(sender As Object, e As EventArgs) Handles Btn9.Click
        TextBox1.Text = TextBox1.Text & "9"
    End Sub

    Private Sub BtnAdd_Click(sender As Object, e As EventArgs) Handles BtnAdd.Click
        total1 = Integer.Parse(TextBox1.Text)
        TextBox1.Clear()

        BtnEquals.Visible = True
        BtnEqual2.Visible = False
        BtnEqual3.Visible = False
        BtnEqual4.Visible = False
    End Sub

    Private Sub BtnMinus_Click(sender As Object, e As EventArgs) Handles BtnMinus.Click
        total1 = Integer.Parse(TextBox1.Text)
        TextBox1.Clear()

        BtnEquals.Visible = False
        BtnEqual2.Visible = True
        BtnEqual3.Visible = False
        BtnEqual4.Visible = False
    End Sub

    Private Sub BtnMultiply_Click(sender As Object, e As EventArgs) Handles BtnMultiply.Click
        total1 = Integer.Parse(TextBox1.Text)
        TextBox1.Clear()

        BtnEquals.Visible = False
        BtnEqual2.Visible = False
        BtnEqual3.Visible = True
        BtnEqual4.Visible = False
    End Sub

    Private Sub BtnDivide_Click(sender As Object, e As EventArgs) Handles BtnDivide.Click
        total1 = Integer.Parse(TextBox1.Text)
        TextBox1.Clear()

        BtnEquals.Visible = False
        BtnEqual2.Visible = False
        BtnEqual3.Visible = False
        BtnEqual4.Visible = True

    End Sub

    Private Sub BtnCLR_Click(sender As Object, e As EventArgs) Handles BtnCLR.Click
        TextBox1.Clear()
        total1 = 0
    End Sub

    Private Sub BtnEquals_Click(sender As Object, e As EventArgs) Handles BtnEquals.Click
        TextBox1.Text = total1 + Integer.Parse(TextBox1.Text)
    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles BtnEqual2.Click
        TextBox1.Text = total1 - Integer.Parse(TextBox1.Text)
    End Sub

    Private Sub BtnEqual3_Click(sender As Object, e As EventArgs) Handles BtnEqual3.Click
        TextBox1.Text = total1 * Integer.Parse(TextBox1.Text)
    End Sub

    Private Sub BtnEqual4_Click(sender As Object, e As EventArgs) Handles BtnEqual4.Click
        TextBox1.Text = total1 / Integer.Parse(TextBox1.Text)
    End Sub

End Class