The document contains the code for a basic calculator application. It defines variables to store the total, operation, and second total. It includes subroutines for each number and operation button that append the value to a text box. The equal button routine performs the calculation based on the stored operation and totals, displays the result, and resets for the next operation.

1. Public Class Form1
Dim total As Double
Dim total1 As Double
Dim operation As String
Private Sub zero_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
zero.Click
TextBox1.Text = TextBox1.Text & zero.Text
End Sub
Private Sub one_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
one.Click
TextBox1.Text = TextBox1.Text & one.Text
End Sub
Private Sub two_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
two.Click
TextBox1.Text = TextBox1.Text & two.Text
End Sub
Private Sub three_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
three.Click
TextBox1.Text = TextBox1.Text & three.Text
End Sub
Private Sub four_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
four.Click
TextBox1.Text = TextBox1.Text & four.Text
End Sub
Private Sub five_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
five.Click
TextBox1.Text = TextBox1.Text & five.Text
End Sub
Private Sub six_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
six.Click
TextBox1.Text = TextBox1.Text & six.Text
End Sub
Private Sub seven_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
seven.Click
TextBox1.Text = TextBox1.Text & seven.Text
End Sub
Private Sub eight_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
eight.Click
TextBox1.Text = TextBox1.Text & eight.Text
End Sub
Private Sub nine_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
nine.Click
TextBox1.Text = TextBox1.Text & nine.Text
End Sub
Private Sub plus_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
plus.Click
operation = "+"

2. total = total + Val(TextBox1.Text)
TextBox1.Text = " "
End Sub
Private Sub Mul_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
Mul.Click
operation = "*"
total = total + Val(TextBox1.Text)
TextBox1.Text = " "
End Sub
Private Sub equal_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
equal.Click
If operation = "+" Then
total1 = total + Val(TextBox1.Text)
total = 0
ElseIf operation = "*" Then
total1 = total * Val(TextBox1.Text)
total = 0
ElseIf operation = "-" Then
total1 = total - Val(TextBox1.Text)
total = 0
ElseIf operation = "" Then
total1 = total Val(TextBox1.Text)
total = 0
End If
TextBox1.Text = total1.ToString()
End Sub
Private Sub minus_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
minus.Click
operation = "-"
total = total + Val(TextBox1.Text)
TextBox1.Text = " "
End Sub
Private Sub div_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
div.Click
operation = ""
total = total + Val(TextBox1.Text)
TextBox1.Text = " "
End Sub
Private Sub Cancel_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
Cancel.Click
TextBox1.Text = " "
End Sub
Private Sub CE_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
CE.Click
TextBox1.Text = ""
total1 = 0
End Sub
Private Sub dot_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles
dot.Click

3. TextBox1.Text = TextBox1.Text & "."
End Sub
End Class