Delphi ActiveX 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. Delphi ActiveX

var
success: Integer;
pdf: TChilkatPdf;
json: TChilkatJsonObject;
jsonOut: TChilkatJsonObject;
pdf2: TChilkatPdf;
json2: TChilkatJsonObject;

begin
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 := TChilkatPdf.Create(Self);
success := pdf.LoadFile('qa_data/pdf/quote_subset_font.pdf');
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf.LastErrorText);
    Exit;
  end;

json := TChilkatJsonObject.Create(Self);
jsonOut := TChilkatJsonObject.Create(Self);

//  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.ControlInterface,jsonOut.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf.LastErrorText);
    Exit;
  end;
Memo1.Lines.Add('58314: ok = ' + IntToStr(Ord(jsonOut.BoolOf('ok'))));

//  ...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.ControlInterface,jsonOut.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf.LastErrorText);
    Exit;
  end;
Memo1.Lines.Add('Q-58341: ok = ' + IntToStr(Ord(jsonOut.BoolOf('ok'))));
if (jsonOut.BoolOf('ok') = 0) then
  begin
    //  The problem names the font and the characters it cannot draw.
    Memo1.Lines.Add('    reason: ' + jsonOut.StringOf('problems[0].reason'));
    Memo1.Lines.Add('    font: ' + jsonOut.StringOf('problems[0].font'));
    Memo1.Lines.Add('    missing: ' + jsonOut.StringOf('problems[0].chars'));
  end;

//  "apply" with a problem returns false and changes nothing.
success := pdf.TextReplace('apply',json.ControlInterface,jsonOut.ControlInterface);
Memo1.Lines.Add('apply returned ' + IntToStr(Ord(success)) + ', applied = ' + IntToStr(Ord(jsonOut.BoolOf('applied'))));

//  2. A font that is not embedded and not one of the standard 14.
pdf2 := TChilkatPdf.Create(Self);
success := pdf2.LoadFile('qa_data/pdf/letter_verdana.pdf');
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf2.LastErrorText);
    Exit;
  end;

json2 := TChilkatJsonObject.Create(Self);
json2.UpdateString('labels[0].label','Account Number:');
json2.UpdateString('labels[0].value','0000099999');
success := pdf2.TextReplace('check',json2.ControlInterface,jsonOut.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf2.LastErrorText);
    Exit;
  end;
Memo1.Lines.Add('Verdana, not embedded: ok = ' + IntToStr(Ord(jsonOut.BoolOf('ok'))) + ', reason: ' + jsonOut.StringOf('problems[0].reason') + ', font: ' + jsonOut.StringOf('problems[0].font'));

//  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