Ruby 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. Ruby

require 'chilkat'

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 = Chilkat::CkPdf.new()
success = pdf.LoadFile("qa_data/pdf/invoice_template.pdf")
if (success == false)
    print pdf.lastErrorText() + "\n";
    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 = Chilkat::CkJsonObject.new()
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 = Chilkat::CkJsonObject.new()
success = pdf.TextReplace("apply",json,jsonOut)
if (success == false)
    print "Not applied: " + jsonOut.emit() + "\n";
    if (success == false)
        print pdf.lastErrorText() + "\n";
        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
    jsonOut.put_I(i)
    print jsonOut.stringOf("replacements[i].field") + ": " + jsonOut.IntOf("replacements[i].count").to_s() + " on page(s) " + jsonOut.stringOf("replacements[i].pages") + "\n";
    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)
    print pdf.lastErrorText() + "\n";
    exit
end

print "Wrote qa_output/invoice_filled.pdf" + "\n";

#  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