B4X 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. B4X

Dim success As Boolean = 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

Dim pdf As ChilkatPdf
pdf.Initialize("pdf")
success = pdf.LoadFile("qa_data/pdf/invoice_template.pdf")
If success = False Then
    Log(pdf.LastErrorText)
    Return
End If


Dim json As ChilkatJsonObject
json.Initialize
Dim jsonOut As ChilkatJsonObject
jsonOut.Initialize

'  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 Then
    Log(pdf.LastErrorText)
    Return
End If

Log("default: " & jsonOut.IntOf("replacements[0].count") & " occurrence replaced")

'  The second occurrence only.
json.UpdateString("labels[0].occurrence", "2")
success = pdf.TextReplace("check", json, jsonOut)
If success = False Then
    Log(pdf.LastErrorText)
    Return
End If

Log("occurrence 2: " & jsonOut.IntOf("replacements[0].count") & " occurrence replaced")

'  Every occurrence.
json.UpdateString("labels[0].occurrence", "all")
success = pdf.TextReplace("apply", json, jsonOut)
If success = False Then
    Log(pdf.LastErrorText)
    Return
End If

Log("occurrence all: " & jsonOut.IntOf("replacements[0].count") & " occurrences replaced")

success = pdf.WriteFile("qa_output/invoice_refs.pdf")
If success = False Then
    Log(pdf.LastErrorText)
    Return
End If


'  Sample output:

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