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Perl Requires Chilkat v11.7.0+

Fill a PDF Template: Replace {{placeholders}} with Values

See more PDF Text Replacement Examples

Demonstrates the TextReplace method on an invoice template whose values are written as placeholders such as {{customer}} and {{total}}. The "placeholders" object names each placeholder and the text to put in; every occurrence on the page is replaced, including a placeholder inside a sentence or inside a label such as "Tax ({{taxRate}}):". The text is redrawn with the font the template used, so the result looks like the template, and a value that is right-aligned in the template stays right-aligned. The changes are written by WriteFile.

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Perl
use chilkat();

$success = 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 invoice_template.pdf

$pdf = chilkat::CkPdf->new();
$success = $pdf->LoadFile("qa_data/pdf/invoice_template.pdf");
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

#  The template has these placeholders in its page text:
#    {{customer}} (twice: "Bill To:" and the closing sentence), {{date}}, {{po}},
#    two item rows: {{qty1}} {{desc1}} {{price1}} {{amount1}} and {{qty2}} {{desc2}} {{price2}} {{amount2}},
#    {{subtotal}}, "Tax ({{taxRate}}):" with {{tax}}, and {{total}}.
$json = chilkat::CkJsonObject->new();
$json->UpdateString("placeholders.customer","Acme Corp");
$json->UpdateString("placeholders.date","2026-10-18");
$json->UpdateString("placeholders.po","PO-88213");
$json->UpdateString("placeholders.qty1","2");
$json->UpdateString("placeholders.desc1","Cordless drill, 18 V");
$json->UpdateString("placeholders.price1","$460.00");
$json->UpdateString("placeholders.amount1","$920.00");
$json->UpdateString("placeholders.qty2","6");
$json->UpdateString("placeholders.desc2","Galvanized hinge, 4 inch");
$json->UpdateString("placeholders.price2","$12.50");
$json->UpdateString("placeholders.amount2","$75.00");
$json->UpdateString("placeholders.subtotal","$995.00");
$json->UpdateString("placeholders.taxRate","7.35%");
$json->UpdateString("placeholders.tax","$73.13");
$json->UpdateString("placeholders.total","$1,068.13");

#  "apply" makes every replacement, or none: if any value cannot be drawn with the
#  template's font, the method returns false, the PDF is unchanged, and jsonOut says why.
$jsonOut = chilkat::CkJsonObject->new();
$success = $pdf->TextReplace("apply",$json,$jsonOut);
if ($success == 0) {
    print "Not applied: " . $jsonOut->emit() . "\r\n";
    if ($success == 0) {
        print $pdf->lastErrorText() . "\r\n";
        exit;
    }

}

#  One entry per placeholder: the pages it was found on and how many times it was replaced.
$i = 0;
$count_i = $jsonOut->SizeOfArray("replacements");
while ($i < $count_i) {
    $jsonOut->put_I($i);
    print $jsonOut->stringOf("replacements[i].field") . ": " . $jsonOut->IntOf("replacements[i].count") . " on page(s) " . $jsonOut->stringOf("replacements[i].pages") . "\r\n";
    $i = $i + 1;
}

#  The replacements stay in memory until the PDF is written.
$success = $pdf->WriteFile("qa_output/invoice_filled.pdf");
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

print "Wrote qa_output/invoice_filled.pdf" . "\r\n";

#  Sample output:

#  customer: 2 on page(s) 1
#  date: 1 on page(s) 1
#  po: 1 on page(s) 1
#  qty1: 1 on page(s) 1
#  desc1: 1 on page(s) 1
#  price1: 1 on page(s) 1
#  amount1: 1 on page(s) 1
#  qty2: 1 on page(s) 1
#  desc2: 1 on page(s) 1
#  price2: 1 on page(s) 1
#  amount2: 1 on page(s) 1
#  subtotal: 1 on page(s) 1
#  taxRate: 1 on page(s) 1
#  tax: 1 on page(s) 1
#  total: 1 on page(s) 1
#  Wrote qa_output/invoice_filled.pdf