Unicode C++ Requires Chilkat v11.7.0+

PDF Placeholders Without a Value: Error, Blank or Keep

See more PDF Text Replacement Examples

Demonstrates the "unusedPlaceholders" option, which decides what happens to a placeholder found on the page that has no value in "placeholders": "error" (the default) makes it a problem with the reason unusedPlaceholder, so nothing is applied; "blank" replaces it with nothing; "keep" leaves it on the page as it is. Unicode C++

#include <CkPdfW.h>
#include <CkJsonObjectW.h>

void ChilkatSample(void)
    {
    bool 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

    CkPdfW pdf;
    success = pdf.LoadFile(L"qa_data/pdf/invoice_template.pdf");
    if (success == false) {
        wprintf(L"%s\n",pdf.lastErrorText());
        return;
    }

    //  Values for every placeholder except {{po}} (the purchase order number, which this customer has none of).
    CkJsonObjectW json;
    json.UpdateString(L"placeholders.customer",L"Acme Corp");
    json.UpdateString(L"placeholders.date",L"2026-10-18");
    json.UpdateString(L"placeholders.qty1",L"2");
    json.UpdateString(L"placeholders.desc1",L"Cordless drill, 18 V");
    json.UpdateString(L"placeholders.price1",L"$460.00");
    json.UpdateString(L"placeholders.amount1",L"$920.00");
    json.UpdateString(L"placeholders.qty2",L"6");
    json.UpdateString(L"placeholders.desc2",L"Galvanized hinge, 4 inch");
    json.UpdateString(L"placeholders.price2",L"$12.50");
    json.UpdateString(L"placeholders.amount2",L"$75.00");
    json.UpdateString(L"placeholders.subtotal",L"$995.00");
    json.UpdateString(L"placeholders.taxRate",L"7.35%");
    json.UpdateString(L"placeholders.tax",L"$73.13");
    json.UpdateString(L"placeholders.total",L"$1,068.13");

    CkJsonObjectW jsonOut;

    //  The default, "error": the unfilled {{po}} is a problem and nothing would be applied.
    success = pdf.TextReplace(L"check",json,jsonOut);
    if (success == false) {
        wprintf(L"%s\n",pdf.lastErrorText());
        return;
    }

    wprintf(L"error (default): ok = %d, problem: %s %s\n",jsonOut.BoolOf(L"ok"),jsonOut.stringOf(L"problems[0].field"),jsonOut.stringOf(L"problems[0].reason"));

    //  "keep": {{po}} stays on the page, literally.
    json.UpdateString(L"unusedPlaceholders",L"keep");
    success = pdf.TextReplace(L"check",json,jsonOut);
    if (success == false) {
        wprintf(L"%s\n",pdf.lastErrorText());
        return;
    }

    wprintf(L"keep: ok = %d\n",jsonOut.BoolOf(L"ok"));

    //  "blank": {{po}} is replaced by nothing, leaving "PO Number:" with an empty value.
    json.UpdateString(L"unusedPlaceholders",L"blank");
    success = pdf.TextReplace(L"apply",json,jsonOut);
    if (success == false) {
        wprintf(L"%s\n",pdf.lastErrorText());
        return;
    }

    wprintf(L"blank: applied = %d\n",jsonOut.BoolOf(L"applied"));

    success = pdf.WriteFile(L"qa_output/invoice_no_po.pdf");
    if (success == false) {
        wprintf(L"%s\n",pdf.lastErrorText());
        return;
    }

    //  Sample output:

    //  error (default): ok = false, problem: po unusedPlaceholder
    //  keep: ok = true
    //  blank: applied = true
    }