Add date-timestamp to PDF

Question

Hi,
Is there a way I could add current date-timestamp to the PDF, when the PDF is opened or printed?
I read the iTEXT documentation and it seems its possible to add javascript to the PDF document using iTEXT and this javascript will get executed when the PDF is opened.
I was successful in adding the "this.print" javascript; however, I am still struggling to figure out how to add "this.addWaterMarkFromText" javascript. I know I can use the iText API to add watermarks, however, I want to use the Adobe Javascript instead. This exercise is just to figure out how to add javascript to PDF.
This would help me figure out how to use various Adobe javascript events such as "WillPrint" to dynamically add the timestamp just before the Print button is clicked.
Any help will be highly appreciated.
Thanks,
Shilpa.

Answer 1

Hi Shilpa,
Please note, I am using C# in my example code, but the solution is similar in Java.
To answer your question regarding using javascript events like Will Print, one way to add a timestamp by first creating a (blank, readonly) field and adding it to your document using iText using, say iTextSharp.text.pdf.TextField. Then you assign javascript to the WillPrint event with writer.SetAdditionalAction(PdfName.WP, PdfAction.JavaScript(jScriptBeforePrint, writer))where writer is an instance of iTextSharp.text.pdf.PdfWriter.
The javascript, in this case jScriptBeforePrint, will change the value of the field you created earlier to contain the date-timestamp value. For example, you can use:
this.getField('datestmp').value =\"This document was printed at \" + util.printd(\"HH:MM on mmmm dd, yyyy\",new Date());where datestmp is the name of the field created earlier.
(by the way Will Print is initiated after the clicking of the print button, not before - as per your post).
Callan