Get-ADUser triggered by Button - winforms

Question

I have a button on a WinForm. After clicking on the button, a function will be called which should execute Get-ADUser cmdlet.
Add-Type -AssemblyName System.Windows.Forms
Add-Type -AssemblyName System.Data
Import-Module ActiveDirectory
$ctl_frm_aduserlist = New-Object System.Windows.Forms.Form -Property #{
Size = New-Object System.Drawing.Size(500,500)
StartPosition = "CenterScreen" }
$ctl_btn_generatepreview = New-Object System.Windows.Forms.Button -Property #{
Size = New-Object System.Drawing.Size(200,30)
Location = New-Object System.Drawing.Point(10,30)
Text = "Generate Preview" }
$ctl_frm_aduserlist.Controls.Add($ctl_btn_generatepreview)
$ctl_btn_generatepreview.Add_Click({ GeneratePreview })
function GeneratePreview(){
Write-Host "GO"
Get-ADUser -Identity "user123" -Properties Name,SamAccountName | select Name,SamAccountName
Write-Host "END" }
$ctl_frm_aduserlist.ShowDialog()
Only the two "Write-Host" cmdlets will be executed by clicking on the button.
If I only execute the single line Get-ADUser in the ISE console, it works and I get the user object.
Why does Get-ADUser not work when triggered via button?
Thanks

Answer 1

First off, I don't have a full solution as I'm not an expert in WinForms, to feel free to correct/complete this answer.
As far as I know, the command is actually executed. You can check it by stepping though the code or Write-Host-ing bits of the object you collected with Get-ADUser and it will display the correct info:
function GeneratePreview() {
Get-ADUser -Identity "someone" | Write-Host
}
Note that if you replace Write-Host by Write-Output it does not work anymore.
The thing is, when you make a WinForms application, the standard output isn't the console anymore. I don't know where it is redirected to, but it's not visible by default. You need to either specify that you want to see your data in the console with write-host, export it to a file (Set-Content, Export-Csv, you name it) or display it in a WinForm element:
I added a new TextBox to your form (called $TextBox1 in my example), and changed GeneratePreview like this:
function GeneratePreview() {
$user = Get-ADUser "someone"
$TextBox1.Text = "$($user.name),$($user.samaccountname)"
}