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JavaScript Requires Chilkat v11.7.0+

What PDF Text Replacement Does Not Change: Metadata, Links, Form Fields

See more PDF Text Replacement Examples

TextReplace changes the page content only. A placeholder that also appears in the document's metadata (the Title, Author, Subject, Keywords, Creator or Producer), in a link's target URL, or in a form field's value is left as it is and reported in "notReplaced" with "where" saying which. The invoice template's title is "Invoice for {{customer}}" and its "View this invoice online" link points at a URL that holds {{customer}}.
Note
This example is intended for running within a Chilkat.Js embedded JavaScript engine. All Chilkat JavaScript examples require Chilkat v11.4.0 or greater.
JavaScript
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 invoice_template.pdf

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

var json = new CkJsonObject();
json.UpdateString("placeholders.customer","Acme Corp");
//  (The other placeholders are left as they are for this example.)
json.UpdateString("unusedPlaceholders","keep");

var jsonOut = new CkJsonObject();
success = pdf.TextReplace("apply",json,jsonOut);
if (success == false) {
    console.log(pdf.LastErrorText);
    return;
}

console.log("In the page content, customer was replaced " + jsonOut.IntOf("replacements[0].count") + " times.");

//  Where else the placeholder occurs, untouched:
var i = 0;
var count_i = jsonOut.SizeOfArray("notReplaced");
while (i < count_i) {
    jsonOut.I = i;
    console.log("not replaced: {{" + jsonOut.StringOf("notReplaced[i].field") + "}} in " + jsonOut.StringOf("notReplaced[i].where"));
    i = i+1;
}

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

//  Sample output:

//  In the page content, customer was replaced 2 times.
//  not replaced: {{customer}} in metadata
//  not replaced: {{customer}} in linkTarget