Powershell Multi-Select List Box Function

I use a bit of code for creating a multiple selection list box from an old technet article (http://technet.microsoft.com/en-us/library/ff730950.aspx) in a number of my powershell scripts.

Recently I was putting together a script on my new Windows 8 box and found that the function no longer returned what was selected. I ended up finding the solution to my problem here.

The issue seems to be related to the way Powershell 3.0 handles variable scopes. To make it work I had to add the script scope to the variable in the function.

Originally the variable was $x, now its $Script:x.

In case anyone finds themselves in the same boat i did here is an updated version of the function.

Function MultipleSelectionBox ($inputarray,$prompt,$listboxtype) {

# Taken from Technet - http://technet.microsoft.com/en-us/library/ff730950.aspx
# This version has been updated to work with Powershell v3.0.
# Had to replace $x with $Script:x throughout the function to make it work. 
# This specifies the scope of the X variable.  Not sure why this is needed for v3.
# http://social.technet.microsoft.com/Forums/en-SG/winserverpowershell/thread/bc95fb6c-c583-47c3-94c1-f0d3abe1fafc
#
# Function has 3 inputs:
#     $inputarray = Array of values to be shown in the list box.
#     $prompt = The title of the list box
#     $listboxtype = system.windows.forms.selectionmode (None, One, MutiSimple, or MultiExtended)

$Script:x = @()

[void] [System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms")
[void] [System.Reflection.Assembly]::LoadWithPartialName("System.Drawing") 

$objForm = New-Object System.Windows.Forms.Form 
$objForm.Text = $prompt
$objForm.Size = New-Object System.Drawing.Size(300,600) 
$objForm.StartPosition = "CenterScreen"

$objForm.KeyPreview = $True

$objForm.Add_KeyDown({if ($_.KeyCode -eq "Enter") 
    {
        foreach ($objItem in $objListbox.SelectedItems)
            {$Script:x += $objItem}
        $objForm.Close()
    }
    })

$objForm.Add_KeyDown({if ($_.KeyCode -eq "Escape") 
    {$objForm.Close()}})

$OKButton = New-Object System.Windows.Forms.Button
$OKButton.Location = New-Object System.Drawing.Size(75,520)
$OKButton.Size = New-Object System.Drawing.Size(75,23)
$OKButton.Text = "OK"

$OKButton.Add_Click(
   {
        foreach ($objItem in $objListbox.SelectedItems)
            {$Script:x += $objItem}
        $objForm.Close()
   })

$objForm.Controls.Add($OKButton)

$CancelButton = New-Object System.Windows.Forms.Button
$CancelButton.Location = New-Object System.Drawing.Size(150,520)
$CancelButton.Size = New-Object System.Drawing.Size(75,23)
$CancelButton.Text = "Cancel"
$CancelButton.Add_Click({$objForm.Close()})
$objForm.Controls.Add($CancelButton)

$objLabel = New-Object System.Windows.Forms.Label
$objLabel.Location = New-Object System.Drawing.Size(10,20) 
$objLabel.Size = New-Object System.Drawing.Size(280,20) 
$objLabel.Text = "Please make a selection from the list below:"
$objForm.Controls.Add($objLabel) 

$objListbox = New-Object System.Windows.Forms.Listbox 
$objListbox.Location = New-Object System.Drawing.Size(10,40) 
$objListbox.Size = New-Object System.Drawing.Size(260,20) 

$objListbox.SelectionMode = $listboxtype

$inputarray | ForEach-Object {[void] $objListbox.Items.Add($_)}

$objListbox.Height = 470
$objForm.Controls.Add($objListbox) 
$objForm.Topmost = $True

$objForm.Add_Shown({$objForm.Activate()})
[void] $objForm.ShowDialog()

Return $Script:x
}