Delphi ActiveX Requires Chilkat v11.7.0+

PDF Placeholders Without a Value: Error, Blank or Keep

See more PDF Text Replacement Examples

Demonstrates the "unusedPlaceholders" option, which decides what happens to a placeholder found on the page that has no value in "placeholders": "error" (the default) makes it a problem with the reason unusedPlaceholder, so nothing is applied; "blank" replaces it with nothing; "keep" leaves it on the page as it is. Delphi ActiveX

var
success: Integer;
pdf: TChilkatPdf;
json: TChilkatJsonObject;
jsonOut: 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 invoice_template.pdf

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

//  Values for every placeholder except {{po}} (the purchase order number, which this customer has none of).
json := TChilkatJsonObject.Create(Self);
json.UpdateString('placeholders.customer','Acme Corp');
json.UpdateString('placeholders.date','2026-10-18');
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');

jsonOut := TChilkatJsonObject.Create(Self);

//  The default, "error": the unfilled {{po}} is a problem and nothing would be applied.
success := pdf.TextReplace('check',json.ControlInterface,jsonOut.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf.LastErrorText);
    Exit;
  end;
Memo1.Lines.Add('error (default): ok = ' + IntToStr(Ord(jsonOut.BoolOf('ok'))) + ', problem: ' + jsonOut.StringOf('problems[0].field') + ' ' + jsonOut.StringOf('problems[0].reason'));

//  "keep": {{po}} stays on the page, literally.
json.UpdateString('unusedPlaceholders','keep');
success := pdf.TextReplace('check',json.ControlInterface,jsonOut.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf.LastErrorText);
    Exit;
  end;
Memo1.Lines.Add('keep: ok = ' + IntToStr(Ord(jsonOut.BoolOf('ok'))));

//  "blank": {{po}} is replaced by nothing, leaving "PO Number:" with an empty value.
json.UpdateString('unusedPlaceholders','blank');
success := pdf.TextReplace('apply',json.ControlInterface,jsonOut.ControlInterface);
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf.LastErrorText);
    Exit;
  end;
Memo1.Lines.Add('blank: applied = ' + IntToStr(Ord(jsonOut.BoolOf('applied'))));

success := pdf.WriteFile('qa_output/invoice_no_po.pdf');
if (success = 0) then
  begin
    Memo1.Lines.Add(pdf.LastErrorText);
    Exit;
  end;

//  Sample output:

//  error (default): ok = false, problem: po unusedPlaceholder
//  keep: ok = true
//  blank: applied = true