Sample code for 30+ languages & platforms
Objective-C Requires Chilkat v11.7.0+

What PDF Text Replacement Does Not Change: Metadata, Links, Form Fields

See more PDF Text Replacement Examples

TextReplace changes the page content only. A placeholder that also appears in the document's metadata (the Title, Author, Subject, Keywords, Creator or Producer), in a link's target URL, or in a form field's value is left as it is and reported in "notReplaced" with "where" saying which. The invoice template's title is "Invoice for {{customer}}" and its "View this invoice online" link points at a URL that holds {{customer}}.

Chilkat Objective-C Downloads

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 is available at invoice_template.pdf

CkoPdf *pdf = [[CkoPdf alloc] init];
success = [pdf LoadFile: @"qa_data/pdf/invoice_template.pdf"];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

CkoJsonObject *json = [[CkoJsonObject alloc] init];
[json UpdateString: @"placeholders.customer" value: @"Acme Corp"];
//  (The other placeholders are left as they are for this example.)
[json UpdateString: @"unusedPlaceholders" value: @"keep"];

CkoJsonObject *jsonOut = [[CkoJsonObject alloc] init];
success = [pdf TextReplace: @"apply" jsonIn: json jsonOut: jsonOut];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

NSLog(@"%@%d%@",@"In the page content, customer was replaced ",[[jsonOut IntOf: @"replacements[0].count"] intValue],@" times.");

//  Where else the placeholder occurs, untouched:
int i = 0;
int count_i = [[jsonOut SizeOfArray: @"notReplaced"] intValue];
while (i < count_i) {
    jsonOut.I = [NSNumber numberWithInt: i];
    NSLog(@"%@%@%@%@",@"not replaced: {{",[jsonOut StringOf: @"notReplaced[i].field"],@"}} in ",[jsonOut StringOf: @"notReplaced[i].where"]);
    i = i + 1;
}

success = [pdf WriteFile: @"qa_output/invoice_customer.pdf"];
if (success == NO) {
    NSLog(@"%@",pdf.LastErrorText);
    return;
}

//  Sample output:

//  In the page content, customer was replaced 2 times.
//  not replaced: {{customer}} in metadata
//  not replaced: {{customer}} in linkTarget