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Node.js Requires Chilkat v11.7.0+

Tile a Watermark Across a PDF Page

See more PDF Watermark Examples

Demonstrates a tiled watermark, which repeats the stamp over the whole page instead of placing it once. Tiling overrides position.align; tile.spacingX and spacingY set the gaps, and tile.stagger offsets alternate rows by half a tile so the pattern does not line up in columns. A faint tiled stamp carrying the name or address is the usual way to mark a document so that a leaked copy can be traced back, and zOrder back keeps it behind the text where it does not hinder reading.

Chilkat Node.js Downloads

Node.js
NODEJS_PRELUDE

function chilkatExample() {

    var 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 long_report.pdf

    var pdf = new chilkat.Pdf();
    success = pdf.LoadFile("qa_data/pdf/long_report.pdf");
    if (success == false) {
        console.log(pdf.LastErrorText);
        return;
    }

    var json = new chilkat.JsonObject();
    json.UpdateString("type","text");

    //  {date:FORMAT} is replaced per page when the watermark is added.  The other placeholders are
    //  {page}, {pages} and {filename}; {{ gives a literal brace.
    json.UpdateString("text","jdoe@example.com  {date:yyyy-MM-dd}");
    json.UpdateString("id","trace");
    json.UpdateString("zOrder","back");
    json.UpdateNumber("font.size","14");
    json.UpdateNumber("opacity","0.15");
    json.UpdateNumber("rotation","30");

    json.UpdateBool("tile.enabled",true);
    json.UpdateNumber("tile.spacingX","60");
    json.UpdateNumber("tile.spacingY","80");
    json.UpdateBool("tile.stagger",true);

    var jsonOut = new chilkat.JsonObject();
    success = pdf.Watermark("add",json,jsonOut);
    if (success == false) {
        console.log(pdf.LastErrorText);
        return;
    }

    console.log("id: " + jsonOut.StringOf("id") + " pages: " + jsonOut.StringOf("pages"));

    success = pdf.WriteFile("qa_output/report_traced.pdf");
    if (success == false) {
        console.log(pdf.LastErrorText);
        return;
    }

    //  Sample output:

    //  id: trace pages: 1-3

}

chilkatExample();