Visual Basic

   Private Sub mnuCalcSale_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuCalcSale.Click<br />
       <br />
            Dim mBookSale As New BookSale<br />
            mBookSale = New BookSale<br />
            With mBookSale<br />
                .Title = txtTitle.Text<br />
                .Quantity = CInt(txtQuantity.Text)<br />
                .Price = CDec(txtPrice.Text)<br />
            End With<br />
            lblExtendedPrice.Text = FormatNumber(mBookSale.ExtendedPrice)<br />
End Sub<br />
<br />

    Private Sub mnuSummary_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles mnuSummary.Click<br />
       <br />
        <br />
        strMessage = "sales Total " & FormatNumber(mBookSale.SalesTotal)<br />
<br />
        MessageBox.Show(strMessage, "Summary Totals", MessageBoxButtons.OK, MessageBoxIcon.Hand)<br />
<br />
    End Sub

Public Class BookSale<br />
    Private mstrTitle As String<br />
    Private mintQuantity As Integer<br />
    Private mdecPrice As Decimal<br />
    Private Shared mdecSalesTotal As Decimal<br />
    Private Shared mintSalesCount As Integer<br />
#Region "Properties"<br />
<br />
<br />
<br />
<br />
    ' below code to set and return or'GET' Title property<br />
    'are properties 'PUBLIC' by default????????<br />
    Public Property Title() As String<br />
        Get<br />
            Title = mstrTitle<br />
        End Get<br />
        Set(ByVal Value As String)<br />
            mstrTitle = Value<br />
        End Set<br />
<br />
    End Property<br />
    Public Property Quantity() As Integer<br />
        Get<br />
            Quantity = mintQuantity<br />
<br />
        End Get<br />
        Set(ByVal Value As Integer)<br />
            If Value >= 0 Then<br />
                mintQuantity = Value<br />
            End If<br />
        End Set<br />
    End Property<br />
    Public Property Price() As Decimal<br />
        Get<br />
            Price = mdecPrice<br />
        End Get<br />
        Set(ByVal Value As Decimal)<br />
            If Value >= 0 Then<br />
                mdecPrice = Value<br />
            End If<br />
        End Set<br />
    End Property<br />
    Public Function ExtendedPrice() As Decimal<br />
        Dim decExtendedPrice As Decimal<br />
        decExtendedPrice = mdecPrice * mintQuantity<br />
        Return decExtendedPrice<br />
        mdecSalesTotal += decExtendedPrice<br />
        mintSalesCount += 1<br />
    End Function<br />
    Public Shared ReadOnly Property SalesTotal() As Decimal<br />
        Get<br />
            If mdecSalesTotal >= 1 Then<br />
            SalesTotal = mdecSalesTotal<br />
            Else<br />
                SalesTotal = 99.99D<br />
            End If<br />
<br />
        End Get<br />
    End Property<br />
    Public Shared ReadOnly Property SalesCount() As Integer<br />
        Get<br />
            SalesCount = mintSalesCount<br />
<br />
        End Get<br />
    End Property<br />
#End Regio