Option Explicit On 
Option Strict On
 
Imports System.DirectoryServices
 
Public Class Form1
    Inherits System.Windows.Forms.Form
 
#Region " Vom Windows Form Designer generierter Code "
 
    Public Sub New()
        MyBase.New()
 
        ' Dieser Aufruf ist für den Windows Form-Designer erforderlich.
        InitializeComponent()
 
        ' Initialisierungen nach dem Aufruf InitializeComponent() hinzufügen
 
    End Sub
 
    ' Die Form überschreibt den Löschvorgang der Basisklasse, um Komponenten zu 
    ' bereinigen.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub
 
    ' Für Windows Form-Designer erforderlich
    Private components As System.ComponentModel.IContainer
 
    'HINWEIS: Die folgende Prozedur ist für den Windows Form-Designer 
    ' erforderlich
    'Sie kann mit dem Windows Form-Designer modifiziert werden.
    'Verwenden Sie nicht den Code-Editor zur Bearbeitung.
    Friend WithEvents Button1 As System.Windows.Forms.Button
    Friend WithEvents TreeView1 As System.Windows.Forms.TreeView
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.Button1 = New System.Windows.Forms.Button
        Me.TreeView1 = New System.Windows.Forms.TreeView
        Me.SuspendLayout()
        '
        'Button1
        '
        Me.Button1.Location = New System.Drawing.Point(280, 8)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New System.Drawing.Size(136, 40)
        Me.Button1.TabIndex = 0
        Me.Button1.Text = "list hosts"
        '
        'TreeView1
        '
        Me.TreeView1.ImageIndex = -1
        Me.TreeView1.Location = New System.Drawing.Point(8, 8)
        Me.TreeView1.Name = "TreeView1"
        Me.TreeView1.SelectedImageIndex = -1
        Me.TreeView1.Size = New System.Drawing.Size(264, 288)
        Me.TreeView1.TabIndex = 1
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(416, 301)
        Me.Controls.Add(Me.TreeView1)
        Me.Controls.Add(Me.Button1)
        Me.Name = "Form1"
        Me.Text = "Form1"
        Me.ResumeLayout(False)
 
    End Sub
 
#End Region
 
    Private Sub listAllHosts()
        Dim childEntry As DirectoryEntry = Nothing
        Dim nodeText As String = Nothing
        Dim ParentEntry As New DirectoryEntry
        Try
            ParentEntry.Path = "WinNT:"
            For Each childEntry In ParentEntry.Children
                Dim newNode As New TreeNode(childEntry.Name)
                Select Case childEntry.SchemaClassName
                    Case "Domain"
                        Dim ParentDomain As New TreeNode(childEntry.Name)
                        TreeView1.Nodes.AddRange(New TreeNode() {ParentDomain})
                        Dim SubChildEntry As DirectoryEntry = Nothing
                        Dim SubParentEntry As New DirectoryEntry
                        SubParentEntry.Path = "WinNT://" + childEntry.Name
                        For Each SubChildEntry In SubParentEntry.Children
                            Try
                                Select Case SubChildEntry.SchemaClassName
                                    Case "Computer"
                                        nodeText = "Name : " + _
                                                                     SubChildEn_
                                                                     try.Name + _
                                                                     " IP: " + _
                                                                     System.Net_
                                                                     .Dns.Resol_
                                                                     ve( _
                                                                     SubChildEn_
                                                                     try.Name)._
                                                                     AddressLis_
                                                                     t(0).ToStr_
                                                                     ing()
                                        Dim newNode1 As New TreeNode(nodeText)
                                        ParentDomain.Nodes.Add(newNode1)
                                End Select
                            Catch ex As Exception
                                Debug.WriteLine("Error: Host " + _
                                  SubChildEntry.Name + " not found..")
                            End Try
                        Next
                End Select
            Next
        Catch Ex As Exception
            MessageBox.Show(Ex.ToString)
        Finally
            ParentEntry = Nothing
        End Try
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
        Me.Text = "Please wait..."
        Me.listAllHosts()
        Me.Text = "Done."
    End Sub
End Class