' Visual Basic 2008 9.0 .NET Examples - Implementation - Object Oriented Programming : 
Namespace Example1
    Class Product
        Private m_Price As Decimal
        Public Property Price() As Decimal
            Get
                Price = m_Price
            End Get
            Set(ByVal value As Decimal)
                m_Price = value
                setPriceIncludingTax()
            End Set
        End Property
        Private m_TaxPercentage As Decimal
        Public Property TaxPercentage() As Decimal
            Get
                TaxPercentage = m_TaxPercentage
            End Get
            Set(ByVal value As Decimal)
                m_TaxPercentage = value
                setPriceIncludingTax()
            End Set
        End Property
        Private m_PriceIncludingTax As Decimal
        Public Function GetPriceIncludingTax() As Decimal
            GetPriceIncludingTax = m_PriceIncludingTax
        End Function
        Private Sub setPriceIncludingTax()
            m_PriceIncludingTax = Price * (1 + (TaxPercentage / 100))
        End Sub
    End Class
    Module Client
        Sub Main()
            Dim product1 As Product = New Product
            product1.Price = 100
            product1.TaxPercentage = 8
            Console.WriteLine(product1.GetPriceIncludingTax())
            '
            Console.ReadLine()
        End Sub
    End Module
End Namespace
Namespace Example2
    Class Product
        Private m_Price As Decimal
        Public Property Price() As Decimal
            Get
                Price = m_Price
            End Get
            Set(ByVal value As Decimal)
                m_Price = value
                setPriceIncludingTax()
            End Set
        End Property
        Private m_TaxPercentage As Decimal
        Public Property TaxPercentage() As Decimal
            Get
                TaxPercentage = m_TaxPercentage
            End Get
            Set(ByVal value As Decimal)
                m_TaxPercentage = value
                setPriceIncludingTax()
            End Set
        End Property
        Private m_PriceIncludingTax As Decimal
        Public ReadOnly Property PriceIncludingTax() As Decimal
            Get
                PriceIncludingTax = m_PriceIncludingTax
            End Get
        End Property
        Private Sub setPriceIncludingTax()
            m_PriceIncludingTax = Price * (1 + (TaxPercentage / 100))
        End Sub
    End Class
    Module Client
        Sub Main()
            Dim product1 As Product = New Product
            product1.Price = 100
            product1.TaxPercentage = 8
            Console.WriteLine(product1.PriceIncludingTax)
            '
            Console.ReadLine()
        End Sub
    End Module
End Namespace
Namespace Exercise1
    Class Addition
        Private m_Value1 As Integer
        Public Property Value1() As Integer
            Get
                Value1 = m_Value1
            End Get
            Set(ByVal value As Integer)
                m_Value1 = value
            End Set
        End Property
        Private m_Value2 As Integer
        Public Property Value2() As Integer
            Get
                Value2 = m_Value2
            End Get
            Set(ByVal value As Integer)
                m_Value2 = value
            End Set
        End Property
        Public Function GetResult() As Integer
            GetResult = Value1 + Value2
        End Function
    End Class
    Module AdditionTestFixture
        Sub Main()
            Dim addition1 As Addition = New Addition
            Console.WriteLine(addition1.Value1 = 0)
            Console.WriteLine(addition1.Value2 = 0)
            Console.WriteLine(addition1.GetResult() = 0)
            '
            addition1.Value1 = 1                                           ' (1)
            Console.WriteLine(addition1.Value1 = 1)
            Console.WriteLine(addition1.Value2 = 0)                        ' (2)
            Console.WriteLine(addition1.GetResult() = 1)
            '
            addition1.Value2 = 2
            Console.WriteLine(addition1.Value1 = 1)
            Console.WriteLine(addition1.Value2 = 2)
            Console.WriteLine(addition1.GetResult() = 3)
            '
            Console.ReadLine()
        End Sub
    End Module
End Namespace
Namespace Exercise2
    Class Lamp
        Private m_GivesLight As Boolean
        Public ReadOnly Property GivesLight() As Boolean
            Get
                GivesLight = m_GivesLight
            End Get
        End Property
        Public Sub PressButton()
            m_GivesLight = Not m_GivesLight
        End Sub
    End Class
    Module LampTestFixture
        Sub Main()
            Dim lamp1 As Lamp = New Lamp
            Console.WriteLine(lamp1.GivesLight = False)
            '
            lamp1.PressButton()
            Console.WriteLine(lamp1.GivesLight = True)
            '
            lamp1.PressButton()
            Console.WriteLine(lamp1.GivesLight = False)
            '
            Console.ReadLine()
        End Sub
    End Module
End Namespace
Namespace Exercise3
    Class Counter
        Private m_Value As Integer
        Public Property Value() As Integer
            Get
                Value = m_Value
            End Get
            Set(ByVal value As Integer)
                m_Value = value
            End Set
        End Property
        Private m_StepValue As Integer = 1
        Public Property StepValue() As Integer
            Get
                StepValue = m_StepValue
            End Get
            Set(ByVal value As Integer)
                m_StepValue = value
            End Set
        End Property
        Public Sub Raise()
            Value += StepValue
        End Sub
        Public Sub Lower()
            Value -= StepValue
        End Sub
    End Class
    Module CounterTestFixture
        Sub Main()
            Dim counter1 As Counter = New Counter
            Console.WriteLine(counter1.Value = 0)
            Console.WriteLine(counter1.StepValue = 1)
            '
            counter1.Value = 10
            Console.WriteLine(counter1.Value = 10)
            Console.WriteLine(counter1.StepValue = 1)
            '
            counter1.StepValue = 5
            Console.WriteLine(counter1.Value = 10)
            Console.WriteLine(counter1.StepValue = 5)
            '
            counter1.Raise()
            Console.WriteLine(counter1.Value = 15)
            Console.WriteLine(counter1.StepValue = 5)
            '
            counter1.Lower()
            Console.WriteLine(counter1.Value = 10)
            Console.WriteLine(counter1.StepValue = 5)
            '
            Console.ReadLine()
        End Sub
    End Module
End Namespace
Namespace Exercise4
    Class Robot
        Private m_X As Integer
        Public ReadOnly Property X() As Integer
            Get
                X = m_X
            End Get
        End Property
        Private m_Y As Integer
        Public ReadOnly Property Y() As Integer
            Get
                Y = m_Y
            End Get
        End Property
        Private m_Direction As Integer
        Public Sub Rotate()
            m_Direction += 1
            If m_Direction > 3 Then m_Direction = 0
        End Sub
        Public Sub PlaceStep()
            Select Case m_Direction
                Case 0 ' up
                    m_Y += 1
                Case 1 ' right
                    m_X += 1
                Case 2 ' down
                    m_Y -= 1
                Case 3 ' left
                    m_X -= 1
            End Select
        End Sub
    End Class
    Module RobotTestFixture
        Public Sub Main()
            Dim robot1 As Robot = New Robot
            Console.WriteLine(robot1.X = 0)
            Console.WriteLine(robot1.Y = 0)
            '
            robot1.PlaceStep()
            Console.WriteLine(robot1.X = 0)
            Console.WriteLine(robot1.Y = 1)
            '
            robot1.PlaceStep()
            Console.WriteLine(robot1.X = 0)
            Console.WriteLine(robot1.Y = 2)
            '
            robot1.Rotate()
            Console.WriteLine(robot1.X = 0)
            Console.WriteLine(robot1.Y = 2)
            '
            robot1.PlaceStep()
            Console.WriteLine(robot1.X = 1)
            Console.WriteLine(robot1.Y = 2)
            '
            robot1.Rotate()
            robot1.PlaceStep()
            Console.WriteLine(robot1.X = 1)
            Console.WriteLine(robot1.Y = 1)
            '
            robot1.Rotate()
            robot1.PlaceStep()
            Console.WriteLine(robot1.X = 0)
            Console.WriteLine(robot1.Y = 1)
            '
            robot1.Rotate()
            robot1.PlaceStep()
            Console.WriteLine(robot1.X = 0)
            Console.WriteLine(robot1.Y = 2)
            '
            Console.ReadLine()
        End Sub
    End Module
End Namespace

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