Imports System.Collections.Generic

Module Module1
    Public Class Generics(Of T)  'Generic class
        Public Sub Swap(Of K)(ByRef lhs As K, ByRef rhs As K)
            'Generic method
            Console.WriteLine("You sent the Swap() method a {0}", GetType(K))

            Dim temp As K 'Local generic data type
            temp = lhs
            lhs = rhs
            rhs = temp
        End Sub

        'Displays the data type and its base type
        Public Sub DisplayBaseClass(Of K)()
            Dim i As Type
            i = GetType(K)
            Console.WriteLine("Base class of {0} is: {1}.", i, i.BaseType)
        End Sub
    End Class

    Sub Main()
        'Service
        'Adding two integars
        Dim g As Generics(Of Integer) = New Generics(Of Integer)
        Dim a As Integer = 2
        Dim b As Integer = -20
        Console.WriteLine("Before swap: {0} , {1}", a, b)
        g.Swap(a, b)
        Console.WriteLine("After swap: {0} , {1}", a, b)
        g.DisplayBaseClass(Of Integer)()

        'Adding two strings
        Dim gb As Generics(Of String) = New Generics(Of String)()
        Dim strA As String = "Hello", strB = "David"
        Console.WriteLine(vbCrLf + "Before swap: {0} {1}", strA, strB)
        g.Swap(strA, strB)
        Console.WriteLine("After swap: {0} {1}", strA, strB)
        g.DisplayBaseClass(Of String)()

        Console.Read()
    End Sub
End Module