Tcl Requires Chilkat v11.7.0+

Replace the Value After a Label in a PDF (Re-issue an Invoice)

See more PDF Text Replacement Examples

Demonstrates replacing the values that follow labels such as "Invoice Number:" on a PDF that has no placeholders -- an ordinary invoice. Each entry of the "labels" array names a label as it appears on the page and the new value; the value replaces the rest of the label's line. Label matching ignores case, extra spaces and a trailing colon. The replaced text is read back with ExtractText to confirm it. Tcl

load ./chilkat.dll

set 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_labels.pdf

set pdf [new_CkPdf]

set success [CkPdf_LoadFile $pdf "qa_data/pdf/invoice_labels.pdf"]
if {$success == 0} then {
    puts [CkPdf_lastErrorText $pdf]
    delete_CkPdf $pdf
    exit
}

#  The invoice has lines such as "Invoice Number:   INV-2026-0412" and "Total Due:  $1,234.53".
#  Each label's new value replaces whatever follows the label on its line.
set json [new_CkJsonObject]

CkJsonObject_UpdateString $json "labels[0].label" "Invoice Number:"
CkJsonObject_UpdateString $json "labels[0].value" "INV-2026-0500"
CkJsonObject_UpdateString $json "labels[1].label" "Invoice Date:"
CkJsonObject_UpdateString $json "labels[1].value" "April 2, 2026"
CkJsonObject_UpdateString $json "labels[2].label" "customer"
CkJsonObject_UpdateString $json "labels[2].value" "Contoso Ltd"
CkJsonObject_UpdateString $json "labels[3].label" "Total Due:"
CkJsonObject_UpdateString $json "labels[3].value" "$1,999.99"

set jsonOut [new_CkJsonObject]

set success [CkPdf_TextReplace $pdf "apply" $json $jsonOut]
if {$success == 0} then {
    puts "Not applied: [CkJsonObject_emit $jsonOut]"
    if {$success == 0} then {
        puts [CkPdf_lastErrorText $pdf]
        delete_CkPdf $pdf
        delete_CkJsonObject $json
        delete_CkJsonObject $jsonOut
        exit
    }

}

set i 0
set count_i [CkJsonObject_SizeOfArray $jsonOut "replacements"]
while {$i < $count_i} {
    CkJsonObject_put_I $jsonOut $i
    puts "Replaced the value of \"[CkJsonObject_stringOf $jsonOut {replacements[i].label}]\" on page [CkJsonObject_stringOf $jsonOut {replacements[i].pages}]"
    set i [expr $i + 1]
}

set success [CkPdf_WriteFile $pdf "qa_output/invoice_reissued.pdf"]
if {$success == 0} then {
    puts [CkPdf_lastErrorText $pdf]
    delete_CkPdf $pdf
    delete_CkJsonObject $json
    delete_CkJsonObject $jsonOut
    exit
}

#  Read the new values back with ExtractText's label option.
set jsonRead [new_CkJsonObject]

set jsonText [new_CkJsonObject]

CkJsonObject_UpdateString $jsonRead "label" "Total Due"
CkJsonObject_UpdateString $jsonRead "labelValue" "right"
set success [CkPdf_ExtractText $pdf "text" $jsonRead $jsonText]
if {$success == 0} then {
    puts [CkPdf_lastErrorText $pdf]
    delete_CkPdf $pdf
    delete_CkJsonObject $json
    delete_CkJsonObject $jsonOut
    delete_CkJsonObject $jsonRead
    delete_CkJsonObject $jsonText
    exit
}

puts "Total Due is now: [CkJsonObject_stringOf $jsonText text]"

#  Sample output:

#  Replaced the value of "Invoice Number:" on page 1
#  Replaced the value of "Invoice Date:" on page 1
#  Replaced the value of "customer" on page 1
#  Replaced the value of "Total Due:" on page 1
#  Total Due is now: $1,999.99

delete_CkPdf $pdf
delete_CkJsonObject $json
delete_CkJsonObject $jsonOut
delete_CkJsonObject $jsonRead
delete_CkJsonObject $jsonText