Visual Basic: Programing Challenge

[Steven97.1]

Hey guys, I'm teaching myself visual basic using the "Starting out with Visual Basic 2012" textbook and I'm having trouble with a two part programing challenge. I did the first part which was:

"An internet service provicer offers 3 subscriptions packages to its customers, plus a discount for nonprofit organizations
a) packaga A: 10 hours of access for $9.95 per month. Additional hpurs are $2.00 per hour.
b)package B: 20 Hours of access for $14.95 per month. Additional hpurs are $1.00 per hpur
c)package C: Unlimited access for $19.95 per month
d)Nonprofit Organizations: the service provider gives all nonprofit prganizations 20% discount on all packages
the user should selelct the package the customer has purchased(from a set of radio buttons) and enter the number of hours used. a check box captioned nonprofit organization should also appear on the form. the application should calculateand display the total amount due. if user selects the nonprofit organization check box a 20% discount should be deducted from the final charges."

I'm stuck on part two, which is:

Using the previous program modify it so the form has a check box captioned Display Potential Savings. When this check box is selected, the application should also display the amount of money that package A customers would save if they purchased package B or C, or the amount that package B customers would save if they purchased package C. If there are no savings, the message should indicate that.

This chapter is about If...Then, If....Then... Else, etc. statements. I don't know where to add or start with this new information given. As well as display it as a string on a Label on the botton of the form.

Public Class Form1

    Private Sub btnExit_Click(sender As Object, e As EventArgs) Handles btnExit.Click
        Me.Close()

    End Sub

    Private Sub btnCalculate_Click(sender As Object, e As EventArgs) Handles btnCalculate.Click
        Dim BasePrice As Decimal
        Dim Hours As Decimal
        Dim AddHours As Decimal
        Dim OverPrice As Decimal
        Dim TotalPrice As Decimal

        Hours = CDec(txtHoursUsed.Text)

        If radPackageA.Checked = True Then
            BasePrice = 9.95
            OverPrice = 2
            AddHours = Hours - 10

            If AddHours < 0 Then
                AddHours = 0
            End If

            TotalPrice = BasePrice + AddHours * OverPrice

        ElseIf radPackageB.Checked = True Then
            BasePrice = 14.95
            OverPrice = 1
            AddHours = Hours - 20

            If AddHours < 0 Then
                AddHours = 0
            End If

            TotalPrice = BasePrice + AddHours * OverPrice

        ElseIf radPackageC.Checked = True Then
            BasePrice = 19.95

            TotalPrice = BasePrice

        End If

        If chkNonprofit.Checked = True Then
            TotalPrice = BasePrice - (BasePrice * 0.2)
        End If

        lblTotalAmountDue.Text = TotalPrice.ToString("C")


    End Sub

    Private Sub btnClear_Click(sender As Object, e As EventArgs) Handles btnClear.Click
        radPackageA.Checked = True

        chkNonprofit.Checked = False

        txtHoursUsed.Clear()

        lblTotalAmountDue.Text = String.Empty

    End Sub
End Class

[tinstaafl]

Basically inside the block for each package, check if the new checkbox is checked then see if the Hours is enough to warrant a savings in the other packages. For instance in package A if the Hours is 25 it would cost 39.95 but package B would only cost 19.95, a savings of 20.00 and package C would be a savings of 20.00.

You might want to split the cost calculation into a function something like:

Private Function GetCost(packagePrice As Decimal, overCost As Decimal, hours as Decimal, limit As Integer) As Decimal

This allows you to clean up the if blocks and reduce duplicate code.