Call javascript from format


is it possible to call a javascript directly from form designer? I tried these steps:

1. fd -> myForm (for myTable)

2. go to myField use this as input: jscall("myJS.myFunc", where is a field of myTable

No syntax error will be returned, but also no result. Could you please help? I only need it in format, not in formatctrl, not in display option etc.