C 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. 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;
    HCkJsonObject jsonRead;
    HCkJsonObject jsonText;

    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_labels.pdf

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

    //  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 = CkJsonObject_Create();
    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");

    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;
        }

    }

    i = 0;
    count_i = CkJsonObject_SizeOfArray(jsonOut,"replacements");
    while (i < count_i) {
        CkJsonObject_putI(jsonOut,i);
        printf("Replaced the value of \"%s\" on page %s\n",CkJsonObject_stringOf(jsonOut,"replacements[i].label"),CkJsonObject_stringOf(jsonOut,"replacements[i].pages"));
        i = i + 1;
    }

    success = CkPdf_WriteFile(pdf,"qa_output/invoice_reissued.pdf");
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf));
        CkPdf_Dispose(pdf);
        CkJsonObject_Dispose(json);
        CkJsonObject_Dispose(jsonOut);
        return;
    }

    //  Read the new values back with ExtractText's label option.
    jsonRead = CkJsonObject_Create();
    jsonText = CkJsonObject_Create();
    CkJsonObject_UpdateString(jsonRead,"label","Total Due");
    CkJsonObject_UpdateString(jsonRead,"labelValue","right");
    success = CkPdf_ExtractText(pdf,"text",jsonRead,jsonText);
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf));
        CkPdf_Dispose(pdf);
        CkJsonObject_Dispose(json);
        CkJsonObject_Dispose(jsonOut);
        CkJsonObject_Dispose(jsonRead);
        CkJsonObject_Dispose(jsonText);
        return;
    }

    printf("Total Due is now: %s\n",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


    CkPdf_Dispose(pdf);
    CkJsonObject_Dispose(json);
    CkJsonObject_Dispose(jsonOut);
    CkJsonObject_Dispose(jsonRead);
    CkJsonObject_Dispose(jsonText);

    }