winforms - Windows forms - add data to list view on button click

Question

I have a winform application which populate some data after I click on $button_UpdateTS, how do I add the data stored in a variable, that comes available after I click on that button ?

The data I want in my list view is stored in an array called $results

$button_UpdateTS = New-Object System.Windows.Forms.Button
$button_UpdateTS.Location = New-Object System.Drawing.Size(15, 954)
$button_UpdateTS.Size = New-Object System.Drawing.Size(320, 32)
$button_UpdateTS.TextAlign = "MiddleCenter"
$button_UpdateTS.Text = “Update Tasksequence”
$button_UpdateTS.Add_Click( { $Results = Set-DynamicVariables 
-Manufacturer "$($listview_Vendor.SelectedItems)" 
-TSPackageID "$($ListView_Tasksequences.SelectedItems.SubItems[1].Text)" -WhatIf })
    $Form.Controls.Add($button_UpdateTS)

Which gives me :

$Results = 
SKUNotExistsDriverName    : XPS Notebook 9560
SKUNotExistsDriverID      : PS10053F
SKUNotExistsDriverSKU     : 07BE
SKUNotExistsDriverVersion : A12
SKUNotExistsBIOSName      : XPS Notebook 9560
SKUNotExistsBIOSID        : PS10053E
SKUNotExistsBIOSSKU       : 07BE
SKUNotExistsBIOSVersion   : 1.15.0

This is the list I want it stored in :

$Global:listview_NotExists_SKU = New-Object System.Windows.Forms.ListView
$listview_NotExists_SKU.Location = New-Object System.Drawing.Size(515, 670)
$listview_NotExists_SKU.Size = New-Object System.Drawing.Size(486, 235)
$listview_NotExists_SKU.View = "Details"
$listview_NotExists_SKU.FullRowSelect = $true
$listview_NotExists_SKU.MultiSelect = $true
$listview_NotExists_SKU.Sorting = "None"
$listview_NotExists_SKU.AllowColumnReorder = $true
$listview_NotExists_SKU.GridLines = $true
$listview_NotExists_SKU.Add_ColumnClick( { SortListView $this $_.Column })
$Form.Controls.Add($listview_NotExists_SKU)

I tried with this function, but that does not work:

Function Get-Results {
        ForEach ($Result in $Results) {
            $listview_NotExists_SKU.Items.Add($Result) 
       }
}

$Form.Add_Shown( { $Form.Load; Get-results })

Answer 1

Because an event-handling script block added with e.g. .Add_Click() runs in in a child scope of the caller, assigning to variable $Results there ($Results = ...) creates a scope-local variable that neither the scope in which the event handler was set up nor subsequently invoked event handlers can see.

To create a variable in the script scope, which subsequently invoked event handlers can see as well^[1], use the $script: scope specifier:

$button_UpdateTS.Add_Click( { $script:Results = ... } )

Note: If the scope in which the event handlers are set up isn't the script scope (e.g., if the code is inside a function) and you want to more generically reference that scope from within an event handler, use Set-Variable -Scope 1 -Name Results -Value ..., which targets the respective parent scope.^[1]

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^{[1] For more information about scopes in PowerShell, see the bottom section of this answer.}