Objective-C Requires Chilkat v11.7.0+

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. Objective-C

#import <CkoPdf.h>
#import <CkoJsonObject.h>

BOOL success = NO;

//  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

CkoPdf *pdf = [[CkoPdf alloc] init];
CkoJsonObject *json = [[CkoJsonObject alloc] init];
CkoJsonObject *jsonOut = [[CkoJsonObject alloc] init];

//  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: @"qa_data/pdf/encrypted_user_password.pdf"];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

//  ...but the content cannot be decrypted, so extracting text fails.
success = [pdf ExtractText: @"text" jsonIn: json jsonOut: jsonOut];
if (success == NO) {
    NSLog(@"%@%@",@"Cannot extract: ",pdf.LastErrorText);
}

//  "assess" still works: it reports that a password is required and nothing else.
success = [pdf ExtractText: @"assess" jsonIn: json jsonOut: jsonOut];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

NSLog(@"%@%d",@"passwordRequired: ",[jsonOut BoolOf: @"quality.passwordRequired"]);
NSLog(@"%@%@",@"rating: ",[jsonOut StringOf: @"quality.rating"]);

//  Set the password and load again.
pdf.UserPassword = @"secret";
success = [pdf LoadFile: @"qa_data/pdf/encrypted_user_password.pdf"];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

success = [pdf ExtractText: @"text" jsonIn: json jsonOut: jsonOut];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

NSLog(@"%@",[jsonOut StringOf: @"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.