Perl Requires Chilkat v11.7.0+

Why a PDF Text Replacement Is Refused: the Font Rule

See more PDF Text Replacement Examples

A PDF stores glyphs drawn with particular fonts, so new text can only be drawn when the original font can draw it. This example shows the two common refusals. A font embedded as a subset carries only the glyphs the document used: a value made of other characters is refused with the reason missingGlyph, and the report names the font and the characters it lacks. A font that is neither one of the standard 14 nor embedded (here Verdana) is refused with nonStandardUnembeddedFont, because Chilkat cannot know what a viewer will draw for it. A non-embedded Arial, Times New Roman or Courier New is treated as the standard font every viewer substitutes for it. 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 quote_subset_font.pdf
#  and letter_verdana.pdf

#  1. An embedded subset font: only the glyphs the document uses are in the PDF.
$pdf = chilkat::CkPdf->new();
$success = $pdf->LoadFile("qa_data/pdf/quote_subset_font.pdf");
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

$json = chilkat::CkJsonObject->new();
$jsonOut = chilkat::CkJsonObject->new();

#  The regular face's subset carries the characters of the quotation's text, among them the digits of
#  "58341".  A new number made of those digits can be drawn...
$json->UpdateString("labels[0].label","Quote #:");
$json->UpdateString("labels[0].value","58314");
$success = $pdf->TextReplace("check",$json,$jsonOut);
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

print "58314: ok = " . $jsonOut->BoolOf("ok") . "\r\n";

#  ...but "Q" and "-" are not in the subset (nothing in the quotation's regular text uses them).
$json->UpdateString("labels[0].value","Q-58341");
$success = $pdf->TextReplace("check",$json,$jsonOut);
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

print "Q-58341: ok = " . $jsonOut->BoolOf("ok") . "\r\n";
if ($jsonOut->BoolOf("ok") == 0) {
    #  The problem names the font and the characters it cannot draw.
    print "    reason: " . $jsonOut->stringOf("problems[0].reason") . "\r\n";
    print "    font: " . $jsonOut->stringOf("problems[0].font") . "\r\n";
    print "    missing: " . $jsonOut->stringOf("problems[0].chars") . "\r\n";
}

#  "apply" with a problem returns false and changes nothing.
$success = $pdf->TextReplace("apply",$json,$jsonOut);
print "apply returned " . $success . ", applied = " . $jsonOut->BoolOf("applied") . "\r\n";

#  2. A font that is not embedded and not one of the standard 14.
$pdf2 = chilkat::CkPdf->new();
$success = $pdf2->LoadFile("qa_data/pdf/letter_verdana.pdf");
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

$json2 = chilkat::CkJsonObject->new();
$json2->UpdateString("labels[0].label","Account Number:");
$json2->UpdateString("labels[0].value","0000099999");
$success = $pdf2->TextReplace("check",$json2,$jsonOut);
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

print "Verdana, not embedded: ok = " . $jsonOut->BoolOf("ok") . ", reason: " . $jsonOut->stringOf("problems[0].reason") . ", font: " . $jsonOut->stringOf("problems[0].font") . "\r\n";

#  Sample output:

#  58314: ok = true
#  Q-58341: ok = false
#      reason: missingGlyph
#      font: AAAAAA+DejaVuSans
#      missing: Q-
#  apply returned false, applied = false
#  Verdana, not embedded: ok = false, reason: nonStandardUnembeddedFont, font: Verdana