Visual Basic

<pre>Public Class frmBaseBallTicketSales
    'Class Variables
    Private _decSeasonBoxSeat As Decimal = 2500D
    Private _decSeasonLowerSeat As Decimal = 1500D
    Private _decSingleBoxSeat As Decimal = 55D
    Private _decSingleLowerSeat As Decimal = 35D
    Private _decUpperSeat As Decimal = 25D
    Private _decStanding As Decimal = 15D
    Private _strSeasonBoxSeats As String = "Box Seats $2500"
    Private _strSeasonLowerDeck As String = "Lower Deck Seats $1500"
    Private _strSingleBoxSeats As String = "Box Seats $55"
    Private _strSingleLowerDeck As String = "Lower Deck Seats $35"
    Private _strUpperDeck As String = "Upper Deck Seats $25"
    Private _strSRO As String = "Standing Room Only $15"

'Make items visible in window.
        Me.lblNumberOfTickets.Visible = True
        Me.txtNumberOfTickets.Visible = True
        Me.lblSeatType.Visible = True
        Me.lstSeats.Visible = True
        Me.btnTicketCost.Visible = True
        Me.btnClear.Visible = True
        Me.lblCost.Visible = True
        'clear labels
        Me.txtNumberOfTickets.Text = ""
        Me.lblSeatType.Text = ""
        Me.lblCost.Text = ""
        'set focus
        Me.txtNumberOfTickets.Focus()

    End Sub

Private Sub SeasonTickets()
        'This procedure fills in the possible seat types for season tickets.
        Me.lstSeats.Items.Add(_strSeasonBoxSeats)
        Me.lstSeats.Items.Add(_strSeasonLowerDeck)
    End Sub
    Private Sub SingleGameTickets()
        'This procedure fills in seat types for single game tickets
        Me.lstSeats.Items.Add(_strSingleBoxSeats)
        Me.lstSeats.Items.Add(_strSingleLowerDeck)
        Me.lstSeats.Items.Add(_strUpperDeck)
        Me.lstSeats.Items.Add(_strSRO)
    End Sub

Private Sub btnTicketCost_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnTicketCost.Click
        'This event handler determines the cost of the tickets chosen.
        'Then it displays the total cost.

        Dim intNumberTix As Integer
        Dim blnNumberTixIsValid As Boolean = False
        Dim blnSeatTypeIsSelected As Boolean = False
        Dim intSeatType As Integer
        Dim strSelectedSeat As String = ""
        Dim decTotalCost As Decimal

        'Call a function to ensure number of tickets is valid.
        blnNumberTixIsValid = ValidateNumberTix()
        'Call a function to make sure ticket type selected.
        intSeatType = ValidateSeatSelection(blnSeatTypeIsSelected, strSelectedSeat)
        'If the number of tickets ordered is valid, calculate the cost.
        If (blnNumberTixIsValid And blnSeatTypeIsSelected) Then
            intSeatType = Me.cboTicketType.SelectedIndex
            Select Case intSeatType
                Case 0
                    decTotalCost = SeasonTicketsFindCost(intSeatType, _
                                                         intNumberTix)
                Case 1
                    decTotalCost = SingleTicketsFindCost(intSeatType, _
                                                         intNumberTix)
            End Select
            'Display Cost.
            lblCost.Text = & decTotalCost.ToString("C")
        End If

    End Sub

Private Function ValidateNumberTix() As Boolean
        'This function validates value entered for number of tickets.
        Dim intNumberOfTix As Integer
        Dim blnValidityCheck As Boolean = False
        Dim strTicketNumberErrorMessage As String = _
        "Please enter the number of tickets you would like to buy (1-20)"
        Dim strMessageBoxTitle As String = "Error"

        Try
            intNumberOfTix = Convert.ToInt32(Me.txtNumberOfTickets.Text)
            If intNumberOfTix > 0 And intNumberOfTix < 21 Then
                blnValidityCheck = True
            Else
                MessageBox.Show(strTicketNumberErrorMessage, _
                strMessageBoxTitle)
                Me.txtNumberOfTickets.Focus()
                Me.txtNumberOfTickets.Clear()
            End If
        Catch Exception As FormatException
            MessageBox.Show(strTicketNumberErrorMessage, _
                            strMessageBoxTitle)
            Me.txtNumberOfTickets.Focus()
            Me.txtNumberOfTickets.Clear()
        Catch Exception As OverflowException
            MessageBox.Show(strTicketNumberErrorMessage, _
                            strMessageBoxTitle)
        Catch Exception As SystemException
            MessageBox.Show(strTicketNumberErrorMessage, _
                            strMessageBoxTitle)
            Me.txtNumberOfTickets.Focus()
            Me.txtNumberOfTickets.Clear()
        End Try

        Return blnValidityCheck

    End Function

Private Function ValidateSeatSelection(ByRef blnType As Boolean, _
                                           ByRef strType As String) As Integer
        'This function makes sure user sleects a seat type.
        Dim intSeatType As Integer
        Try
            intSeatType = Convert.ToInt32(Me.lstSeats.SelectedIndex)
            strType = Me.lstSeats.SelectedItem.ToString()
            blnType = True
        Catch Exception As SystemException
            'Detects if seat type not selected.
            MessageBox.Show("Select a seat type", "Error")
            blnType = False
        End Try
        Return intSeatType

    End Function

Private Function SeasonTicketsFindCost(ByVal intSeatType As Integer, _
                                           ByVal intNumberTix As Integer) As Decimal
        'This function will calculate cost of season tickets.
        Dim decTotalCost As Decimal
        Dim decSeatCost As Decimal
        Dim decNumberTix As Decimal

        Select Case intSeatType
            Case 0
                decSeatCost = _decSeasonBoxSeat
                decNumberTix = intNumberTix
            Case 1
                decSeatCost = _decSeasonLowerSeat
                decNumberTix = intNumberTix
        End Select
        decTotalCost = decSeatCost * decNumberTix
        Return decTotalCost

    End Function

Private Function SingleTicketsFindCost(ByVal intseattype As Integer, _
                                           ByVal intNumberTix As Integer) As Decimal
        'This function will calvulate the cost of single tickets.
        Dim decTotalCost As Decimal
        Dim DecSeatCost As Decimal
        Dim decNumberTix As Decimal

        Select Case intseattype
            Case 0
                DecSeatCost = _decSingleBoxSeat
                decNumberTix = intNumberTix
            Case 1
                DecSeatCost = _decSingleLowerSeat
                decNumberTix = intNumberTix
            Case 2
                DecSeatCost = _decStanding
                decNumberTix = intNumberTix
            Case 3
                DecSeatCost = _decUpperSeat
                decNumberTix = intNumberTix
        End Select
        decTotalCost = DecSeatCost * intNumberTix
        Return decTotalCost

    End Function

Private Sub btnClear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClear.Click
        'This event handler clears the form and resets the form for reuse,
        'when user clicks the clear button.
        Me.cboTicketType.Text = "Select Ticket Type"
        Me.txtNumberOfTickets.Clear()
        Me.lstSeats.Items.Clear()
        Me.lblCost.Visible = False
        Me.lblTotalCost.Visible = False

    End Sub

 Private Sub frmBaseBallTicketSales_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'This handler creates 5 seconds for the splash screen
        Threading.Thread.Sleep(5000)
    End Sub

End Class