C 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. C

#include <C_CkPdf.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkPdf pdf;
    HCkJsonObject json;
    HCkJsonObject jsonOut;
    int i;
    int count_i;

    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

    pdf = CkPdf_Create();
    success = CkPdf_LoadFile(pdf,"qa_data/pdf/invoice_template.pdf");
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf));
        CkPdf_Dispose(pdf);
        return;
    }

    //  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 = CkJsonObject_Create();
    CkJsonObject_UpdateString(json,"placeholders.customer","Acme Corp");
    CkJsonObject_UpdateString(json,"placeholders.date","2026-10-18");
    CkJsonObject_UpdateString(json,"placeholders.po","PO-88213");
    CkJsonObject_UpdateString(json,"placeholders.qty1","2");
    CkJsonObject_UpdateString(json,"placeholders.desc1","Cordless drill, 18 V");
    CkJsonObject_UpdateString(json,"placeholders.price1","$460.00");
    CkJsonObject_UpdateString(json,"placeholders.amount1","$920.00");
    CkJsonObject_UpdateString(json,"placeholders.qty2","6");
    CkJsonObject_UpdateString(json,"placeholders.desc2","Galvanized hinge, 4 inch");
    CkJsonObject_UpdateString(json,"placeholders.price2","$12.50");
    CkJsonObject_UpdateString(json,"placeholders.amount2","$75.00");
    CkJsonObject_UpdateString(json,"placeholders.subtotal","$995.00");
    CkJsonObject_UpdateString(json,"placeholders.taxRate","7.35%");
    CkJsonObject_UpdateString(json,"placeholders.tax","$73.13");
    CkJsonObject_UpdateString(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 = CkJsonObject_Create();
    success = CkPdf_TextReplace(pdf,"apply",json,jsonOut);
    if (success == FALSE) {
        printf("Not applied: %s\n",CkJsonObject_emit(jsonOut));
        if (success == FALSE) {
            printf("%s\n",CkPdf_lastErrorText(pdf));
            CkPdf_Dispose(pdf);
            CkJsonObject_Dispose(json);
            CkJsonObject_Dispose(jsonOut);
            return;
        }

    }

    //  One entry per placeholder: the pages it was found on and how many times it was replaced.
    i = 0;
    count_i = CkJsonObject_SizeOfArray(jsonOut,"replacements");
    while (i < count_i) {
        CkJsonObject_putI(jsonOut,i);
        printf("%s: %d on page(s) %s\n",CkJsonObject_stringOf(jsonOut,"replacements[i].field"),CkJsonObject_IntOf(jsonOut,"replacements[i].count"),CkJsonObject_stringOf(jsonOut,"replacements[i].pages"));
        i = i + 1;
    }

    //  The replacements stay in memory until the PDF is written.
    success = CkPdf_WriteFile(pdf,"qa_output/invoice_filled.pdf");
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf));
        CkPdf_Dispose(pdf);
        CkJsonObject_Dispose(json);
        CkJsonObject_Dispose(jsonOut);
        return;
    }

    printf("Wrote qa_output/invoice_filled.pdf\n");

    //  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_Dispose(pdf);
    CkJsonObject_Dispose(json);
    CkJsonObject_Dispose(jsonOut);

    }