' Visual Basic 2008 9.0 .NET Examples - Extension Methods - New in Visual Basic 2008 - 9.0 : 
Public Module PersonExtension
    <System.Runtime.CompilerServices.Extension()> _
    Public Sub Print(ByVal aPerson As Person)
        If aPerson IsNot Nothing Then
            Console.WriteLine("Istance of Person : " & aPerson.ToString())
        Else
            Console.WriteLine("No instance of Person.")
        End If
    End Sub
End Module
Public Class Person
    Private m_Name As String
    Public Property Name() As String
        Get
            Name = m_Name
        End Get
        Set(ByVal value As String)
            m_Name = value
        End Set
    End Property
    Public Overrides Function ToString() As String
        ToString = Name
    End Function
End Class
Public Class Student : Inherits Person
    Private m_ClassGroup As String
    Public Property ClassGroup() As String
        Get
            ClassGroup = m_ClassGroup
        End Get
        Set(ByVal value As String)
            m_ClassGroup = value
        End Set
    End Property
    Public Overrides Function ToString() As String
        ToString = Name & " (" & ClassGroup & ")"
    End Function
End Class
Public Class Example1
    Public Shared Sub Main()
        Dim person1 As Person = New Person With {.Name = "John"}
        Dim person2 As Person = New Student _
                                With {.Name = "Jane", _
                                      .ClassGroup = "Visual Basic .NET"}
        Dim person3 As Person
        '
        person1.Print()                                                    ' (1)
        person2.Print()
        person3.Print()
        '
        Console.ReadLine()
    End Sub
End Class
' Visit www.studyvb.com for more examples.  Copyright 2003-2008 De Wolf.