PowerShell

Sign PDF with Invisible Signature

See more PDF Signatures Examples

Demonstrates how to sign a PDF with an invisible signature.

Note: This example requires Chilkat v9.5.0.85 or greater.

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.

$pdf = New-Object Chilkat.Pdf

# Load a PDF to be signed.
# The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
$success = $pdf.LoadFile("qa_data/pdf/hello.pdf")
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

# Options for signing are specified in JSON.
$json = New-Object Chilkat.JsonObject

# In most cases, the signingCertificateV2 and signingTime attributes are required.
$json.UpdateInt("signingCertificateV2",1)
$json.UpdateInt("signingTime",1)

# Indicate that the signature will be invisible.
$json.UpdateBool("invisibleSignature",$true)

# Load the signing certificate. (Use your own certificate.)
$cert = New-Object Chilkat.Cert
$success = $cert.LoadPfxFile("qa_data/pfx/myPdfSigningCert.pfx","secret")
if ($success -eq $false) {
    $($cert.LastErrorText)
    exit
}

# Tell the pdf object to use the certificate for signing.
$success = $pdf.SetSigningCert($cert)
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$success = $pdf.SignPdf($json,"qa_output/hello_signed.pdf")
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$("PDF successfully signed with an invisible signature.")

# An invisible signature has no appearance within the PDF document itself,
# but Adobe Acrobat will indicate the document is signed in a toolbar, as shown here:
# (image:https://example-code.com/images/invisible_signature.jpg/endImage)