Lazarus Pascal 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. Lazarus Pascal

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.Pdf,
  Chilkat.JsonObject;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  pdf: TPdf;
  json: TJsonObject;
  jsonOut: TJsonObject;
  i: Integer;
  count_i: Integer;

begin
  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 is available at invoice_template.pdf

  pdf := TPdf.Create;
  success := pdf.LoadFile('qa_data/pdf/invoice_template.pdf');
  if (success = False) then
    begin
      WriteLn(pdf.LastErrorText);
      Exit;
    end;

  //  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 := TJsonObject.Create;
  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 := TJsonObject.Create;
  success := pdf.TextReplace('apply',json,jsonOut);
  if (success = False) then
    begin
      WriteLn('Not applied: ' + jsonOut.Emit());
      if (success = False) then
        begin
          WriteLn(pdf.LastErrorText);
          Exit;
        end;
    end;

  //  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 do
    begin
      jsonOut.I := i;
      WriteLn(jsonOut.StringOf('replacements[i].field') + ': ' + jsonOut.IntOf('replacements[i].count') + ' on page(s) ' + jsonOut.StringOf('replacements[i].pages'));
      i := i + 1;
    end;

  //  The replacements stay in memory until the PDF is written.
  success := pdf.WriteFile('qa_output/invoice_filled.pdf');
  if (success = False) then
    begin
      WriteLn(pdf.LastErrorText);
      Exit;
    end;
  WriteLn('Wrote qa_output/invoice_filled.pdf');

  //  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


  pdf.Free;
  json.Free;
  jsonOut.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.