Powershell - 2 x Listbox - synchron scrollen

Add-Type -MemberDefinition @'  
Public Class MyListBox
    Inherits ListBox
    Public Delegate Sub MyListBoxScrollDelegate(Sender As Object, e As MyListBoxScrollArgs)
    Public Event Scroll As MyListBoxScrollDelegate
    ' WM_VSCROLL constants  
    Private Const WM_VSCROLL As Integer = &H115
    Private Const SB_THUMBTRACK As Integer = 5
    Private Const SB_ENDSCROLL As Integer = 8
    Protected Overrides Sub WndProc(ByRef m As Message)
    	' Trap the WM_VSCROLL message to generate the Scroll event  
    	MyBase.WndProc(m)
    	If m.Msg = WM_VSCROLL Then
    		Dim nfy As Integer = m.WParam.ToInt32() And &Hffff
    		If (nfy = SB_THUMBTRACK OrElse nfy = SB_ENDSCROLL) Then
    			RaiseEvent Scroll(Me, New MyListBoxScrollArgs(Me.TopIndex, nfy = SB_THUMBTRACK))
    		End If
    	End If
    End Sub
    Public Class MyListBoxScrollArgs
    	Private mTop As Integer
    	Private mTracking As Boolean
    	Public Sub New(top As Integer, tracking As Boolean)
    		mTop = top
    		mTracking = tracking
    	End Sub
    	Public ReadOnly Property Top() As Integer
    		Get
    			Return mTop
    		End Get
    	End Property
    	Public ReadOnly Property Tracking() As Boolean
    		Get
    			Return mTracking
    		End Get
    	End Property
    End Class
End Class
'@ -name tools -Namespace Win32 -Language VisualBasic -ReferencedAssemblies "System.Windows.Forms" -UsingNamespace "System.Windows.Forms" -EA SilentlyContinue  


function GenerateForm {

#region Import the Assemblies
[reflection.assembly]::loadwithpartialname("System.Windows.Forms") | Out-Null  
[reflection.assembly]::loadwithpartialname("System.Drawing") | Out-Null  
#endregion

#region Generated Form Objects
$form1 = New-Object System.Windows.Forms.Form
$listBox2 = New-Object Win32.tools+MyListBox
$listBox1 = New-Object Win32.tools+MyListBox
$InitialFormWindowState = New-Object System.Windows.Forms.FormWindowState
#endregion Generated Form Objects

#region Generated Form Code
$System_Drawing_Size = New-Object System.Drawing.Size
$System_Drawing_Size.Height = 196
$System_Drawing_Size.Width = 334
$form1.ClientSize = $System_Drawing_Size
$form1.DataBindings.DefaultDataSourceUpdateMode = 0
$form1.FormBorderStyle = 3
$form1.MaximizeBox = $False
$form1.MinimizeBox = $False
$form1.Name = "form1"  
$form1.Text = "Synced Scrolling"  

$listBox2.DataBindings.DefaultDataSourceUpdateMode = 0
$listBox2.FormattingEnabled = $True
$System_Drawing_Point = New-Object System.Drawing.Point
$System_Drawing_Point.X = 169
$System_Drawing_Point.Y = 12
$listBox2.Location = $System_Drawing_Point
$listBox2.Name = "listBox2"  
$listBox2.ScrollAlwaysVisible = $True
$System_Drawing_Size = New-Object System.Drawing.Size
$System_Drawing_Size.Height = 173
$System_Drawing_Size.Width = 153
$listBox2.Size = $System_Drawing_Size
$listBox2.TabIndex = 1
$listBox2.Items.AddRange(1..200)
$listbox2.add_KeyDown({
    $listbox1.TopIndex = $listBox2.TopIndex
})
$listbox2.add_Scroll({
  $listbox1.TopIndex = $_.Top  
})

$form1.Controls.Add($listBox2)

$listBox1.DataBindings.DefaultDataSourceUpdateMode = 0
$listBox1.FormattingEnabled = $True
$System_Drawing_Point = New-Object System.Drawing.Point
$System_Drawing_Point.X = 12
$System_Drawing_Point.Y = 12
$listBox1.Location = $System_Drawing_Point
$listBox1.Name = "listBox1"  
$listBox1.ScrollAlwaysVisible = $True
$System_Drawing_Size = New-Object System.Drawing.Size
$System_Drawing_Size.Height = 173
$System_Drawing_Size.Width = 151
$listBox1.Size = $System_Drawing_Size
$listBox1.TabIndex = 0
$listBox1.Items.AddRange(1..200)
$listbox1.add_KeyDown({
    $listbox2.TopIndex = $listBox1.TopIndex
})
$listbox1.add_Scroll({
  $listbox2.TopIndex = $_.Top  
})
$form1.Controls.Add($listBox1)


#Save the initial state of the form
$InitialFormWindowState = $form1.WindowState
#Init the OnLoad event to correct the initial state of the form
$form1.add_Load($OnLoadForm_StateCorrection)
#Show the Form
$form1.ShowDialog()| Out-Null

} #End Function
GenerateForm