How to change the name of the attachment in an email

Hello,

I am able to send out an email from my PDF by using a submit button. I use the following javascript for it:

var vMailToAddress = "Leon [dot] Boeijen [at] nl4b [dot] com"; //Mandatory
var vMailCcAddress = ""; //Optional
var vMailBccAddress = ""; //Optional
var vMailSubject = "This is a copy of your pdf"; //Optional
var vMailBody = ""; //Optional, Within the body use "%0A" for a new line,
// use "%0A%0A" for a new line preceded by a blank line (paragraph)

var vTarget = "mailto:" + vMailToAddress + "?subject=" + vMailSubject + "&body=" + vMailBody + "&cc=" + vMailCcAddress + "&bcc=" + vMailBccAddress;
this.resolveNode("#event").submit.target = vTarget;

And I have set the Send as option to 'PDF'.

This will send out an email with the full PDF as an attachment and uses the current pdf filename as the name of the attachement.

Only I want to change the name of the attached file based on data inside the PDF that can be set by the user.

Can anyone help me?

I use Adobe LifeCycle Designer ES 8.2 and am able to use FormCalc and Javascript.

Thanks in advance.