PureBasic 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. PureBasic

IncludeFile "CkPdf.pb"
IncludeFile "CkJsonObject.pb"

Procedure ChilkatExample()

    success.i = 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

    pdf.i = CkPdf::ckCreate()
    If pdf.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkPdf::ckLoadFile(pdf,"qa_data/pdf/invoice_labels.pdf")
    If success = 0
        Debug CkPdf::ckLastErrorText(pdf)
        CkPdf::ckDispose(pdf)
        ProcedureReturn
    EndIf

    ;  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.
    json.i = CkJsonObject::ckCreate()
    If json.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

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

    jsonOut.i = CkJsonObject::ckCreate()
    If jsonOut.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    success = CkPdf::ckTextReplace(pdf,"apply",json,jsonOut)
    If success = 0
        Debug "Not applied: " + CkJsonObject::ckEmit(jsonOut)
        If success = 0
            Debug CkPdf::ckLastErrorText(pdf)
            CkPdf::ckDispose(pdf)
            CkJsonObject::ckDispose(json)
            CkJsonObject::ckDispose(jsonOut)
            ProcedureReturn
        EndIf

    EndIf

    i.i = 0
    count_i.i = CkJsonObject::ckSizeOfArray(jsonOut,"replacements")
    While i < count_i
        CkJsonObject::setCkI(jsonOut, i)
        Debug "Replaced the value of " + Chr(34) + CkJsonObject::ckStringOf(jsonOut,"replacements[i].label") + Chr(34) + " on page " + CkJsonObject::ckStringOf(jsonOut,"replacements[i].pages")
        i = i + 1
    Wend

    success = CkPdf::ckWriteFile(pdf,"qa_output/invoice_reissued.pdf")
    If success = 0
        Debug CkPdf::ckLastErrorText(pdf)
        CkPdf::ckDispose(pdf)
        CkJsonObject::ckDispose(json)
        CkJsonObject::ckDispose(jsonOut)
        ProcedureReturn
    EndIf

    ;  Read the new values back with ExtractText's label option.
    jsonRead.i = CkJsonObject::ckCreate()
    If jsonRead.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    jsonText.i = CkJsonObject::ckCreate()
    If jsonText.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckUpdateString(jsonRead,"label","Total Due")
    CkJsonObject::ckUpdateString(jsonRead,"labelValue","right")
    success = CkPdf::ckExtractText(pdf,"text",jsonRead,jsonText)
    If success = 0
        Debug CkPdf::ckLastErrorText(pdf)
        CkPdf::ckDispose(pdf)
        CkJsonObject::ckDispose(json)
        CkJsonObject::ckDispose(jsonOut)
        CkJsonObject::ckDispose(jsonRead)
        CkJsonObject::ckDispose(jsonText)
        ProcedureReturn
    EndIf

    Debug "Total Due is now: " + CkJsonObject::ckStringOf(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


    CkPdf::ckDispose(pdf)
    CkJsonObject::ckDispose(json)
    CkJsonObject::ckDispose(jsonOut)
    CkJsonObject::ckDispose(jsonRead)
    CkJsonObject::ckDispose(jsonText)


    ProcedureReturn
EndProcedure