Проверка деления на ноль в калькуляторе - Visual Basic .NET

Public Class Form1
    Dim FirstNumber As Single
    Dim SecondNumber As Single
    Dim AnswerNumber As Single
    Dim ArithemeticProcess As String
 
    Private Sub Button10_Click(sender As Object, e As EventArgs) Handles Button10.Click
        TextBox1.Text = TextBox1.Text & "0"
    End Sub
 
    Private Sub Button11_Click(sender As Object, e As EventArgs) Handles Button11.Click
        TextBox1.Text = TextBox1.Text & ","
    End Sub
 
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        TextBox1.Text = TextBox1.Text & "1"
    End Sub
 
    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        TextBox1.Text = TextBox1.Text & "2"
    End Sub
 
    Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
        TextBox1.Text = TextBox1.Text & "3"
    End Sub
 
    Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
        TextBox1.Text = TextBox1.Text & "4"
    End Sub
 
    Private Sub Button5_Click(sender As Object, e As EventArgs) Handles Button5.Click
        TextBox1.Text = TextBox1.Text & "5"
    End Sub
 
    Private Sub Button6_Click(sender As Object, e As EventArgs) Handles Button6.Click
        TextBox1.Text = TextBox1.Text & "6"
    End Sub
 
    Private Sub Button7_Click(sender As Object, e As EventArgs) Handles Button7.Click
        TextBox1.Text = TextBox1.Text & "7"
    End Sub
 
    Private Sub Button8_Click(sender As Object, e As EventArgs) Handles Button8.Click
        TextBox1.Text = TextBox1.Text & "8"
    End Sub
 
    Private Sub Button9_Click(sender As Object, e As EventArgs) Handles Button9.Click
        TextBox1.Text = TextBox1.Text & "9"
    End Sub
 
    Private Sub Button17_Click(sender As Object, e As EventArgs) Handles Button17.Click
        TextBox1.Clear()
    End Sub
 
    Private Sub Button13_Click(sender As Object, e As EventArgs) Handles Button13.Click
        FirstNumber = Val(TextBox1.Text)
        TextBox1.Text = ""
        ArithemeticProcess = "+"
    End Sub
 
    Private Sub Button14_Click(sender As Object, e As EventArgs) Handles Button14.Click
        FirstNumber = Val(TextBox1.Text)
        TextBox1.Text = ""
        ArithemeticProcess = "-"
    End Sub
 
    Private Sub Button16_Click(sender As Object, e As EventArgs) Handles Button16.Click
        FirstNumber = Val(TextBox1.Text)
        TextBox1.Text = ""
        ArithemeticProcess = "*"
    End Sub
 
    Private Sub Button15_Click(sender As Object, e As EventArgs) Handles Button15.Click
        FirstNumber = Val(TextBox1.Text)
        TextBox1.Text = ""
        ArithemeticProcess = "/"
    End Sub
 
    Private Sub Button12_Click(sender As Object, e As EventArgs) Handles Button12.Click
        SecondNumber = Val(TextBox1.Text)
        If ArithemeticProcess = "+" Then
            AnswerNumber = FirstNumber + SecondNumber
        End If
        SecondNumber = Val(TextBox1.Text)
        If ArithemeticProcess = "-" Then
            AnswerNumber = FirstNumber - SecondNumber
        End If
        SecondNumber = Val(TextBox1.Text)
        If ArithemeticProcess = "*" Then
            AnswerNumber = FirstNumber * SecondNumber
        End If
        SecondNumber = Val(TextBox1.Text)
        If ArithemeticProcess = "/" Then
            AnswerNumber = FirstNumber / SecondNumber
        End If
        TextBox1.Text = AnswerNumber
    End Sub
End Class