Friend Class Tree
    Friend Root As Directory
    Friend NumFiles As Integer
    Friend NoDirectory As Boolean
End Class
Friend MustInherit Class FileObject
    Protected m_list As New List(Of FileObject)
    Private m_Name As String
    Private m_FullName As String
    Public Property Name As String
        Get
            Return m_name
        End Get
        Set(ByVal value As String)
            m_name = value
        End Set
    End Property
    Public Property FullName As String
        Get
            Return m_FullName
        End Get
        Set(ByVal value As String)
            m_FullName = value
        End Set
    End Property
End Class
Friend Class File
    Inherits FileObject
    Private m_len As ULong
    Public ReadOnly Property Len As ULong
        Get
            Return m_len
        End Get
    End Property
    Public Sub New(ByVal FullName As String)
        If IO.File.Exists(FullName) Then
            Dim File As New IO.FileInfo(FullName)
            Me.Name = File.Name
            Me.FullName = FullName
            m_len = File.Length
        Else
            Throw New Exception(FullName & " is not a file")
        End If
    End Sub
End Class
Friend Class Directory
    Inherits FileObject
    Public Sub New(ByVal FullName As String)
        If IO.Directory.Exists(FullName) Then
            Dim File As New IO.FileInfo(FullName)
            Me.Name = File.Name
            Me.FullName = FullName
        Else
            Throw New Exception(FullName & " is not a file")
        End If
    End Sub
    Public ReadOnly Property Items As List(Of FileObject)
        Get
            Return m_list
        End Get
    End Property
End Class