(Lianja) Certify a PDF and Lock the Entire Document

See more PDF Signatures Examples

This example demonstrates how to a sign a certify a PDF and lock the entire document. Normally this is intended to seal the document with a final approving (or dissapproving) signature; usually after a review workflow is completed and normally reserved for the creator or author of a document.

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

loPdf = createobject("CkPdf")

// Load a PDF to be certified and locked.
// The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
llSuccess = loPdf.LoadFile("qa_data/pdf/hello.pdf")
if (llSuccess = .F.) then
    ? loPdf.LastErrorText
    release loPdf
    return
endif

// Options for signing are specified in JSON.
loJson = createobject("CkJsonObject")

// In most cases, the signingCertificateV2 and signingTime attributes are required.
loJson.UpdateInt("signingCertificateV2",1)
loJson.UpdateInt("signingTime",1)

// The only coding difference with certifying and locking a PDF
// as compared with an approval signature (also known as recipient signature)
// is to add the "lockAfterSigning" and "docMDP.add" to the json.
loJson.UpdateBool("lockAfterSigning",.T.)
loJson.UpdateBool("docMDP.add",.T.)

// Put the signature on page 1, top left
loJson.UpdateInt("page",1)
loJson.UpdateString("appearance.y","top")
loJson.UpdateString("appearance.x","left")

// Use a font scale of 10.0
loJson.UpdateString("appearance.fontScale","10.0")

// In this example, the appearance of the digital signature will contain three lines:
// 1) The signing certificate's common name
// 2) The current date/time
// 3) Some arbitrary text.
// The keyword "cert_cn" is replaced with the Certificate's Subject Common Name.
// The keyword "current_dt" is replaced with the current date/time.
// Any number of appearance text lines can be added.
loJson.UpdateString("appearance.text[0]","Digitally signed by: cert_cn")
loJson.UpdateString("appearance.text[1]","current_dt")
loJson.UpdateString("appearance.text[2]","The crazy brown fox jumps over the lazy dog.")

// Load the signing certificate. (Use your own certificate.)
loCert = createobject("CkCert")
llSuccess = loCert.LoadPfxFile("qa_data/pfx/myPdfSigningCert.pfx","secret")
if (llSuccess = .F.) then
    ? loCert.LastErrorText
    release loPdf
    release loJson
    release loCert
    return
endif

// Tell the pdf object to use the certificate for signing.
llSuccess = loPdf.SetSigningCert(loCert)
if (llSuccess = .F.) then
    ? loPdf.LastErrorText
    release loPdf
    release loJson
    release loCert
    return
endif

llSuccess = loPdf.SignPdf(loJson,"qa_output/hello_signed.pdf")
if (llSuccess = .F.) then
    ? loPdf.LastErrorText
    release loPdf
    release loJson
    release loCert
    return
endif

? "The PDF has been successfully certified and locked."


release loPdf
release loJson
release loCert