PowerShell Requires Chilkat v11.7.0+

Find Out Whether a PDF Needs a Password Before Loading It

See more PDF Protection Examples

Demonstrates PreLoadCheck, which examines a PDF file without loading it and without any password. It reports whether the file is encrypted, by which method and algorithm, whether a password is needed to open it, and what its permissions are. An application uses it to decide whether to ask for a password, or which certificate it needs, before calling LoadFile. PreLoadCheckBd does the same for a PDF held in memory. PowerShell

Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

#  This example requires the Chilkat API to have been previously unlocked.
#  See Global Unlock Sample for sample code.

#  The PDF used in this example is available at two_page_memo.pdf

#  The PDF used in this example is available at encrypted_user_password.pdf

#  The PDF used in this example is available at no_copy_permission.pdf

$pdf = New-Object Chilkat.Pdf
$info = New-Object Chilkat.JsonObject

#  A PDF that is not encrypted.  Nothing but "encrypted" is reported for it.
$success = $pdf.PreLoadCheck("qa_data/pdf/two_page_memo.pdf",$info)
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$("two_page_memo.pdf")
$("  encrypted: " + $info.BoolOf("encrypted"))

#  A PDF that needs a password to open.
$success = $pdf.PreLoadCheck("qa_data/pdf/encrypted_user_password.pdf",$info)
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$("encrypted_user_password.pdf")
$("  encrypted: " + $info.BoolOf("encrypted"))
$("  method: " + $info.StringOf("method"))
$("  algorithm: " + $info.StringOf("algorithm"))
$("  openPasswordRequired: " + $info.BoolOf("openPasswordRequired"))

#  A PDF that opens without a password but is restricted.  The permissions are readable without
#  any password.
$success = $pdf.PreLoadCheck("qa_data/pdf/no_copy_permission.pdf",$info)
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$("no_copy_permission.pdf")
$("  encrypted: " + $info.BoolOf("encrypted"))
$("  openPasswordRequired: " + $info.BoolOf("openPasswordRequired"))
$("  may copy: " + $info.BoolOf("permissions.copy"))

#  The typical use: ask for a password only when one is needed, then load.
$success = $pdf.PreLoadCheck("qa_data/pdf/encrypted_user_password.pdf",$info)
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

if ($info.BoolOf("openPasswordRequired") -eq $true) {
    #  An application would prompt for the password here.
    $pdf.UserPassword = "secret"
}

$success = $pdf.LoadFile("qa_data/pdf/encrypted_user_password.pdf")
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$("loaded, pages: " + $pdf.NumPages)

#  Sample output:

#  two_page_memo.pdf
#    encrypted: False
#  encrypted_user_password.pdf
#    encrypted: True
#    method: password
#    algorithm: rc4-128
#    openPasswordRequired: True
#  no_copy_permission.pdf
#    encrypted: True
#    openPasswordRequired: False
#    may copy: False
#  loaded, pages: 1