PHP Extension Requires Chilkat v11.7.0+

Get Every Occurrence of a Label in a PDF

See more PDF Text Extraction Examples

Demonstrates the "labelOccurrence" option. When the same label appears more than once (for example "Total:" on each of several receipts), "first" (the default) uses the first occurrence, "all" returns every occurrence with its page, and a number selects one occurrence. PHP Extension

<?php

include("chilkat.php");

$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 (three receipts, one per page) is available at three_receipts.pdf

$pdf = new CkPdf();
$success = $pdf->LoadFile('qa_data/pdf/three_receipts.pdf');
if ($success == false) {
    print $pdf->lastErrorText() . "\n";
    exit;
}

$json = new CkJsonObject();
$jsonOut = new CkJsonObject();

//  Each of the three pages is a receipt with a "Total:" line.
$json->UpdateString('label','Total');
$json->UpdateString('labelValue','right');

//  By default only the first occurrence (in reading order) is used.
$success = $pdf->ExtractText('text',$json,$jsonOut);
if ($success == false) {
    print $pdf->lastErrorText() . "\n";
    exit;
}

print 'First total: ' . $jsonOut->stringOf('text') . "\n";

//  labelOccurrence "all" returns every occurrence.  The "text" member holds the values joined
//  by line breaks, and labelMatches has one entry per occurrence with its page.
$json->UpdateString('labelOccurrence','all');
$success = $pdf->ExtractText('text',$json,$jsonOut);
if ($success == false) {
    print $pdf->lastErrorText() . "\n";
    exit;
}

$i = 0;
$count_i = $jsonOut->SizeOfArray('labelMatches');
while ($i < $count_i) {
    $jsonOut->put_I($i);
    print 'Page ' . $jsonOut->IntOf('labelMatches[i].page') . ' total: ' . $jsonOut->stringOf('labelMatches[i].text') . "\n";
    $i = $i + 1;
}

//  A number selects one occurrence: 2 is the second.
$json->UpdateInt('labelOccurrence',2);
$success = $pdf->ExtractText('text',$json,$jsonOut);
if ($success == false) {
    print $pdf->lastErrorText() . "\n";
    exit;
}

print 'Second total: ' . $jsonOut->stringOf('text') . "\n";

//  The occurrences are counted over the selected pages, so combining "pages" with the label
//  is another way to pick one receipt:
$json->UpdateString('labelOccurrence','first');
$json->UpdateString('pages','3');
$json->UpdateString('label','Receipt No.');
$success = $pdf->ExtractText('text',$json,$jsonOut);
if ($success == false) {
    print $pdf->lastErrorText() . "\n";
    exit;
}

print 'Receipt number on page 3: ' . $jsonOut->stringOf('text') . "\n";

//  Sample output:

//  First total: $19.86
//  Page 1 total: $19.86
//  Page 2 total: $17.34
//  Page 3 total: $23.62
//  Second total: $17.34
//  Receipt number on page 3: 1003

?>