Script to replace Placeholders with Values in Editable Form in PDF

pdf.php

<?php

/*#############################
* Developer: Mohammad Sharaf Ali
* Designation: Web Developer
* Version: 1.0
*/#############################

/* REQUIREMENTS
 * https://www.pdflabs.com/tools/pdftk-server/
 * https://github.com/mikehaertl/php-pdftk
 * If on windows -> place the files (pdftk.exe, libiconv2.dll) in your working directory
 */

require_once 'vendor/autoload.php';

use mikehaertl\pdftk\Pdf;

### STEP 1: get total no of pages
$pdf = new Pdf('sample.pdf');
$data = $pdf->getData();
$pages = 0;

if (preg_match('/NumberOfPages: (\d+)/', $data, $match)) {
    $pages = $match[1];
}

### STEP 2: split each page into single file
// if provided single multi-page file, pdftk will cater form fields of first page only
for ($i = 1; $i <= $pages; $i++) {
    // you can also use $pdf->burst()
    $pdf = new Pdf('sample.pdf');
    $pdf->cat(array($i))
        ->saveAs('sample_' . $i . '.pdf');
}

### STEP 3: replace placeholders in each file
for ($i = 1; $i <= $pages; $i++) {
    $pdf = new Pdf('sample_' . $i . '.pdf');
    $dataFields = $pdf->getDataFields();
    $fillForm = [];

    foreach ($dataFields as $dataField) {
        if (isset($dataField['FieldStateOption'])) { // handle dropdown, radio, & checkbox inputs
            $fillForm[$dataField['FieldName']] = $dataField['FieldStateOption'][1];
        } else { // handle text inputs
            $fillForm[$dataField['FieldName']] = mt_rand(1, 100000);
        }
    }

    $pdf = new Pdf('sample_' . $i . '.pdf');
    $pdf->fillForm($fillForm)
        ->flatten() // if you need final file to be un-editable
        //->needAppearances() // if you need final file to be editable
        ->saveAs('sample_' . $i . '.pdf');
}

### STEP 4: merge splitted files into a single file
$pdf = new Pdf();

for ($i = 1; $i <= $pages; $i++) {
    $pdf->addFile('sample_' . $i . '.pdf');
}

$pdf->saveAs('sample_final.pdf');

### Step5: remove splitted files
for ($i = 1; $i <= $pages; $i++) {
    unlink('sample_' . $i . '.pdf');
}