Unicode C++ Requires Chilkat v11.7.0+
Unicode C++
Extract Text from a Password-Protected PDF
See more PDF Text Extraction Examples
Demonstrates extracting text from a PDF that requires a password to open. The PDF loads without the password (its structure can be read), but the "text" operation fails because the content cannot be decrypted; "assess" reports that a password is required. With the UserPassword property set before loading, extraction works normally.Chilkat Unicode C++ Downloads
#include <CkPdfW.h>
#include <CkJsonObjectW.h>
void ChilkatSample(void)
{
bool 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 (user password: secret) is available at encrypted_user_password.pdf
CkPdfW pdf;
CkJsonObjectW json;
CkJsonObjectW jsonOut;
// The PDF loads without its password: the file's structure is readable, so properties such as
// NumPages and the security settings are available...
success = pdf.LoadFile(L"qa_data/pdf/encrypted_user_password.pdf");
if (success == false) {
wprintf(L"%s\n",pdf.lastErrorText());
return;
}
// ...but the content cannot be decrypted, so extracting text fails.
success = pdf.ExtractText(L"text",json,jsonOut);
if (success == false) {
wprintf(L"Cannot extract: %s\n",pdf.lastErrorText());
}
// "assess" still works: it reports that a password is required and nothing else.
success = pdf.ExtractText(L"assess",json,jsonOut);
if (success == false) {
wprintf(L"%s\n",pdf.lastErrorText());
return;
}
wprintf(L"passwordRequired: %d\n",jsonOut.BoolOf(L"quality.passwordRequired"));
wprintf(L"rating: %s\n",jsonOut.stringOf(L"quality.rating"));
// Set the password and load again.
pdf.put_UserPassword(L"secret");
success = pdf.LoadFile(L"qa_data/pdf/encrypted_user_password.pdf");
if (success == false) {
wprintf(L"%s\n",pdf.lastErrorText());
return;
}
success = pdf.ExtractText(L"text",json,jsonOut);
if (success == false) {
wprintf(L"%s\n",pdf.lastErrorText());
return;
}
wprintf(L"%s\n",jsonOut.stringOf(L"text"));
// Sample output:
// Cannot extract: ChilkatLog:
// ExtractText:
// ...
// The PDF is encrypted and could not be opened (wrong or missing password); its text cannot be read.
// ...
// passwordRequired: true
// rating: none
// Board Minutes (Confidential)
//
// The board met on 3 November 2026. Present: the chair, the treasurer and four members. The treasurer reported that spending for the season came in under budget.
//
// The meeting closed at 8.45 p.m.
}