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Unicode C++ Requires Chilkat v11.7.0+

Page Numbers, Dates and the File Name in a PDF Watermark

See more PDF Watermark Examples

Demonstrates the placeholders a text watermark understands, each replaced per page as the watermark is added: {page} is the page number, {pages} the page count, {date:FORMAT} the current local date and time, and {filename} the name of the file that was loaded. Two braces give a literal brace. pageNumber.start sets what {page} is on the first page, which is how a numbering that ignores a cover is produced, and pageNumber.style formats both {page} and {pages} as decimal, romanUpper, romanLower, letterUpper or letterLower.

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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 four_pages.pdf

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

    CkJsonObjectW json;
    json.UpdateString(L"type",L"text");
    json.UpdateString(L"text",L"Page {page} of {pages}  -  printed {date:yyyy-MM-dd HH:mm}  -  {filename}");
    json.UpdateString(L"id",L"pagefoot");
    json.UpdateString(L"position.align",L"bottom");
    json.UpdateNumber(L"position.margin",L"24");
    json.UpdateNumber(L"font.size",L"9");
    json.UpdateString(L"color",L"#505050");

    CkJsonObjectW jsonOut;
    success = pdf.Watermark(L"add",json,jsonOut);
    if (success == false) {
        wprintf(L"%s\n",pdf.lastErrorText());
        return;
    }

    wprintf(L"footer pages: %s\n",jsonOut.stringOf(L"pages"));

    //  Roman numerals that start at i on page 2, so that a cover page is not numbered.
    CkPdfW pdf2;
    success = pdf2.LoadFile(L"qa_data/pdf/four_pages.pdf");
    if (success == false) {
        wprintf(L"%s\n",pdf2.lastErrorText());
        return;
    }

    CkJsonObjectW json2;
    json2.UpdateString(L"type",L"text");
    json2.UpdateString(L"text",L"- {page} -");
    json2.UpdateString(L"id",L"roman");
    json2.UpdateString(L"pages",L"2-");
    json2.UpdateInt(L"pageNumber.start",1);
    json2.UpdateString(L"pageNumber.style",L"romanLower");
    json2.UpdateString(L"position.align",L"bottom");
    json2.UpdateNumber(L"font.size",L"10");
    success = pdf2.Watermark(L"add",json2,jsonOut);
    if (success == false) {
        wprintf(L"%s\n",pdf2.lastErrorText());
        return;
    }

    wprintf(L"roman pages: %s\n",jsonOut.stringOf(L"pages"));

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

    //  Sample output:

    //  footer pages: 1-4
    //  roman pages: 2-4
    }