Ruby Requires Chilkat v11.7.0+

Replace the Second (or Every) Occurrence of a Label in a PDF

See more PDF Text Replacement Examples

Demonstrates the "occurrence" member of a label entry. By default the first occurrence of a label, in reading order across the selected pages, is replaced; "occurrence" can be a number for the nth, or "all" for every occurrence. The invoice template has "Ref:" twice. 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

json = Chilkat::CkJsonObject.new()
jsonOut = Chilkat::CkJsonObject.new()

#  This template's {{placeholders}} are not being filled here: "keep" leaves them as they are
#  (the default, "error", would refuse to apply while a placeholder on the page has no value).
json.UpdateString("unusedPlaceholders","keep")

#  "Ref:" appears twice on the page (A-1 near the top, A-2 below the totals).
#  The default replaces the first occurrence only.
json.UpdateString("labels[0].label","Ref:")
json.UpdateString("labels[0].value","B-7")
success = pdf.TextReplace("check",json,jsonOut)
if (success == false)
    print pdf.lastErrorText() + "\n";
    exit
end

print "default: " + jsonOut.IntOf("replacements[0].count").to_s() + " occurrence replaced" + "\n";

#  The second occurrence only.
json.UpdateString("labels[0].occurrence","2")
success = pdf.TextReplace("check",json,jsonOut)
if (success == false)
    print pdf.lastErrorText() + "\n";
    exit
end

print "occurrence 2: " + jsonOut.IntOf("replacements[0].count").to_s() + " occurrence replaced" + "\n";

#  Every occurrence.
json.UpdateString("labels[0].occurrence","all")
success = pdf.TextReplace("apply",json,jsonOut)
if (success == false)
    print pdf.lastErrorText() + "\n";
    exit
end

print "occurrence all: " + jsonOut.IntOf("replacements[0].count").to_s() + " occurrences replaced" + "\n";

success = pdf.WriteFile("qa_output/invoice_refs.pdf")
if (success == false)
    print pdf.lastErrorText() + "\n";
    exit
end

#  Sample output:

#  default: 1 occurrence replaced
#  occurrence 2: 1 occurrence replaced
#  occurrence all: 2 occurrences replaced