Xbase++ Requires Chilkat v11.7.0+

Password-Protect a PDF with AES-256 Encryption

See more PDF Protection Examples

Demonstrates the simplest way to encrypt a PDF so that it needs a password to open. The passwords come from the UserPassword and OwnerPassword properties, and Protection with the encrypt operation and an empty JSON uses the defaults: AES-256, everything encrypted, every permission granted. Protection only records the security the PDF will be saved with. Nothing is encrypted until WriteFile is called. Xbase++

LOCAL nSuccess
LOCAL oPdf
LOCAL oJson
LOCAL oJsonOut
LOCAL oChecker
LOCAL oInfo
LOCAL oReader

nSuccess := 0

//  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

oPdf := CreateObject("Chilkat.Pdf")
nSuccess := oPdf:LoadFile("qa_data/pdf/two_page_memo.pdf")
IF (nSuccess == 0)
    ? oPdf:LastErrorText
    oPdf:destroy()
    RETURN
ENDIF

//  The passwords are taken from these two properties at the time Protection is called.
//  The user password opens the PDF.  The owner password opens it too, and is the one needed
//  later to change or remove the protection.
oPdf:UserPassword := "user-secret"
oPdf:OwnerPassword := "owner-secret"

//  An empty JSON asks for the defaults: AES-256, everything encrypted, every permission granted.
oJson := CreateObject("Chilkat.JsonObject")
oJsonOut := CreateObject("Chilkat.JsonObject")
nSuccess := oPdf:Protection("encrypt", oJson, oJsonOut)
IF (nSuccess == 0)
    ? oPdf:LastErrorText
    oPdf:destroy()
    oJson:destroy()
    oJsonOut:destroy()
    RETURN
ENDIF

//  Nothing has been encrypted yet.  "pending" describes the security the PDF will be saved with.
? "algorithm: " + oJsonOut:StringOf("pending.algorithm")
? "PDF version: " + oJsonOut:StringOf("pending.pdfVersion")
? "password needed to open: " + Str(oJsonOut:BoolOf("pending.userPasswordRequired"))

//  Writing the file applies it.
nSuccess := oPdf:WriteFile("qa_output/memo_encrypted.pdf")
IF (nSuccess == 0)
    ? oPdf:LastErrorText
    oPdf:destroy()
    oJson:destroy()
    oJsonOut:destroy()
    RETURN
ENDIF

//  PreLoadCheck reports a file's encryption without loading it, and needs no password.
oChecker := CreateObject("Chilkat.Pdf")
oInfo := CreateObject("Chilkat.JsonObject")
nSuccess := oChecker:PreLoadCheck("qa_output/memo_encrypted.pdf", oInfo)
IF (nSuccess == 0)
    ? oChecker:LastErrorText
    oPdf:destroy()
    oJson:destroy()
    oJsonOut:destroy()
    oChecker:destroy()
    oInfo:destroy()
    RETURN
ENDIF

? "encrypted: " + Str(oInfo:BoolOf("encrypted"))
? "openPasswordRequired: " + Str(oInfo:BoolOf("openPasswordRequired"))

//  With the password, the PDF opens normally.
oReader := CreateObject("Chilkat.Pdf")
oReader:UserPassword := "user-secret"
nSuccess := oReader:LoadFile("qa_output/memo_encrypted.pdf")
IF (nSuccess == 0)
    ? oReader:LastErrorText
    oPdf:destroy()
    oJson:destroy()
    oJsonOut:destroy()
    oChecker:destroy()
    oInfo:destroy()
    oReader:destroy()
    RETURN
ENDIF

? "pages: " + Str(oReader:NumPages)

//  Sample output:

//  algorithm: aes-256
//  PDF version: 1.7
//  password needed to open: True
//  encrypted: True
//  openPasswordRequired: True
//  pages: 2

oPdf:destroy()
oJson:destroy()
oJsonOut:destroy()
oChecker:destroy()
oInfo:destroy()
oReader:destroy()