Powershell pervent GUI from closing when executing a application with a button - powershell

Question

In my Powershell GUI i'd like to press a button and open notepad without having the GUI closing in the background.
The dialog closes immediately with the following code
$button.Add_Click({Start-Process notepad.exe $file}) ;
When using -Wait the dialog will stay open until i close notepad but still close the
$button.Add_Click({Start-Process -Wait notepad.exe $file}) ;
The same happens when using variables
$button.Add_Click({& $notepad $file}) ;
the following is the full code block:
$file = '*\file.txt'
Add-Type -AssemblyName System.Windows.Forms
Add-Type -AssemblyName System.Drawing
$form = New-Object System.Windows.Forms.Form
$form.Text = "Don't close"
$form.Size = New-Object System.Drawing.Size(280,160)
$form.StartPosition = 'CenterScreen'
$form.FormBorderStyle = 'FixedDialog'
$form.Topmost = $true
$form.MaximizeBox = $false
$form.MinimizeBox = $false
$button = New-Object System.Windows.Forms.Button
$button.Location = New-Object System.Drawing.Point(20,40)
$button.Size = New-Object System.Drawing.Size(160,23)
$button.Text = "button"
$button.DialogResult = [System.Windows.Forms.DialogResult]::OK
$form.AcceptButton = $button
$form.Controls.Add($button)
$button.Add_Click({Start-Process -Wait notepad.exe $file}) ;
$form.ShowDialog()
Where am i going wrong?

Answer 1

This is because you are setting the button to be the Form's AcceptButton and also the control that gets the DialogResult.
Simply remove two lines (to show which ones, I add the code commented out below).
Then, also do not use the -Wait switch on the Start-Process.
The code adjusted:
$file = 'D:\blah.txt'
Add-Type -AssemblyName System.Windows.Forms
Add-Type -AssemblyName System.Drawing
$form = New-Object System.Windows.Forms.Form
$form.Text = "Don't close"
$form.Size = New-Object System.Drawing.Size(280,160)
$form.StartPosition = 'CenterScreen'
$form.FormBorderStyle = 'FixedDialog'
$form.Topmost = $true
$form.MaximizeBox = $false
$form.MinimizeBox = $false
$button = New-Object System.Windows.Forms.Button
$button.Location = New-Object System.Drawing.Point(20,40)
$button.Size = New-Object System.Drawing.Size(160,23)
$button.Text = "button"
# drop these two lines
# $button.DialogResult = [System.Windows.Forms.DialogResult]::OK
# $form.AcceptButton = $button
$form.Controls.Add($button)
# do not use the -Wait parameter on Start-Process here
$button.Add_Click({Start-Process notepad.exe $file}) ;
$form.ShowDialog()
$form.Dispose()