PowerShell: PPT to PDF - Recurse

.\ppt2pdf.ps1

<#
.Synopsis
  ConverToPDF converts PowerPoint files to pdf and saves the output into the \pdf current folder.
.DESCRIPTION
  ConverToPDF converts PowerPoint files to pdf and saves the output into the \pdf current folder.
.NOTES
  Created by: Paul Lim paullim@ncs.com.sg
  Modified: 18/03/2019
  Changelog:
   * First version
  To Do:
   *
.PARAMETER None
  None
.EXAMPLE
    Run this script under the same folder as all the PowerPoint files.
    It will open each PPTX file and saves it as PDF under a newly created \pdf folder.
.LINK
#>
# Create folder to store pdf output
New-Item -Path $PSScriptRoot\pdf -ItemType directory -Force
Get-ChildItem $PSScriptRoot -File -Filter *pptx -Recurse |
ForEach-Object -Begin {
    $null = Add-Type -AssemblyName Microsoft.Office.Interop.PowerPoint
    $SaveOption = [Microsoft.Office.Interop.PowerPoint.PpSaveAsFileType]::ppSaveAsPDF
    $PowerPoint = New-Object -ComObject "PowerPoint.Application"
} -Process {
    $Presentation = $PowerPoint.Presentations.Open($_.FullName)
    $PdfNewName  = $PSScriptRoot + "\\pdf\\" + $_.Name -replace '\.pptx$','.pdf'
    $Presentation.SaveAs($PdfNewName,$SaveOption)
    $Presentation.Close()
} -End {
    $PowerPoint.Quit()
    Stop-Process -Name POWERPNT -Force
}