Sample code for 30+ languages & platforms
PureBasic 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.

Chilkat PureBasic Downloads

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_template.pdf

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

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

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

    CkJsonObject::ckUpdateString(json,"placeholders.customer","Acme Corp")
    CkJsonObject::ckUpdateString(json,"placeholders.date","2026-10-18")
    CkJsonObject::ckUpdateString(json,"placeholders.po","PO-88213")
    CkJsonObject::ckUpdateString(json,"placeholders.qty1","2")
    CkJsonObject::ckUpdateString(json,"placeholders.desc1","Cordless drill, 18 V")
    CkJsonObject::ckUpdateString(json,"placeholders.price1","$460.00")
    CkJsonObject::ckUpdateString(json,"placeholders.amount1","$920.00")
    CkJsonObject::ckUpdateString(json,"placeholders.qty2","6")
    CkJsonObject::ckUpdateString(json,"placeholders.desc2","Galvanized hinge, 4 inch")
    CkJsonObject::ckUpdateString(json,"placeholders.price2","$12.50")
    CkJsonObject::ckUpdateString(json,"placeholders.amount2","$75.00")
    CkJsonObject::ckUpdateString(json,"placeholders.subtotal","$995.00")
    CkJsonObject::ckUpdateString(json,"placeholders.taxRate","7.35%")
    CkJsonObject::ckUpdateString(json,"placeholders.tax","$73.13")
    CkJsonObject::ckUpdateString(json,"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.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

    ;  One entry per placeholder: the pages it was found on and how many times it was replaced.
    i.i = 0
    count_i.i = CkJsonObject::ckSizeOfArray(jsonOut,"replacements")
    While i < count_i
        CkJsonObject::setCkI(jsonOut, i)
        Debug CkJsonObject::ckStringOf(jsonOut,"replacements[i].field") + ": " + Str(CkJsonObject::ckIntOf(jsonOut,"replacements[i].count")) + " on page(s) " + CkJsonObject::ckStringOf(jsonOut,"replacements[i].pages")
        i = i + 1
    Wend

    ;  The replacements stay in memory until the PDF is written.
    success = CkPdf::ckWriteFile(pdf,"qa_output/invoice_filled.pdf")
    If success = 0
        Debug CkPdf::ckLastErrorText(pdf)
        CkPdf::ckDispose(pdf)
        CkJsonObject::ckDispose(json)
        CkJsonObject::ckDispose(jsonOut)
        ProcedureReturn
    EndIf

    Debug "Wrote qa_output/invoice_filled.pdf"

    ;  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


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


    ProcedureReturn
EndProcedure