On the main form field tab, clicking the SHOW JAVASCRIPT OPTIONS, displays the JavaScript options for the form field.
 
Each event can have a different JavaScript script that gets triggered. See the Adobe PDF Specification for information on JavaScript syntax.
(http://partners.adobe.com/asn/acrobat/sdk/public/docs/AcroJS.pdf)
It is very similar to standard JavaScript as used in HTML.
 
Clicking the Form Field tab again will return you to the main form field tab.
 
Note: PDFtypewriter does not check JavaScript syntax.
 
See Form Field Object (7 of 7)