Get and display a random image under a base folder

Random-gen.ps1

# supply the root of your image archive folder as a parameter (or edit this file and hard-code $archiveroot)

param([String]$archiveroot="$env:TEMP") 

Add-Type -AssemblyName 'System.Windows.Forms'
Add-Type -AssemblyName 'System.Drawing.Common'

$path = dir -recurse "$($archiveroot)\*.*" | Get-random | % {$_.FullName}
write-host $path

try {
  $file = (get-item $path)
  $img = [System.Drawing.Image]::Fromfile((get-item $file))

  [System.Windows.Forms.Application]::EnableVisualStyles()
  $form = new-object Windows.Forms.Form
  $form.Text = "Image Viewer " + $path
  $form.Width = $img.Size.Width;
  $form.Height =  $img.Size.Height;
  $pictureBox = new-object Windows.Forms.PictureBox
  $pictureBox.Width =  $img.Size.Width;
  $pictureBox.Height =  $img.Size.Height;

  $pictureBox.Image = $img;
  $form.controls.add($pictureBox)
  $form.Add_Shown( { $form.Activate() } )
  $form.ShowDialog() | Out-Null
  $img.Dispose()
} catch { Start-process $file }