ーーーーVB.net でのインターフェイスの使い方ーーーー

Module Module1
    Sub Main()
        Dim hito(2) As hito
        hito(0) = New inaba()
        hito(1) = New ichikawa()
        Console.WriteLine(hito(1).getName)
        hito(0).MsgName()
    End Sub
End Module

Public Interface hito
    Sub MsgName()
    Function getName() As String
End Interface

Public Class inaba : Implements hito
    Const name As String = "inabaです"
    Sub Msgname() Implements hito.MsgName
        MsgBox(name)
    End Sub
    Function getName() As String Implements hito.getName
        Return name
    End Function
End Class

Public Class ichikawa : Implements hito
    Const name As String = "ichikawaです"
    Sub Msgname() Implements hito.MsgName
        MsgBox(name)
    End Sub
    Function getName() As String Implements hito.getName
        Return name
    End Function
End Class

ーーーーオーバーロードも可能ーーーー
Class a
    Public Sub test(ByVal a As Integer)
        MsgBox(a)
    End Sub
    Public Sub test(ByVal a As String)
        MsgBox(a)
    End Sub
    Public Function test2(ByVal a As Int32) As String
        Return a.ToString
    End Function
    Public Function test2(ByVal a As String) As String
        Return a
    End Function
End Class