Conditionally Required Fields

Question

Basics -
Running LC ES 8.2 and Acrobat 9 Pro and using Acrobat for this form.
Novice/Beginner in JavaScripting as a whole, especially as pertains to PDFs
Situation -
Trying  to set up a form wherein a field is required if one option from a combo  box is selected and to either be optional or removed otherwise.
I've  been trying "if ... else" statements without any luck. The field  (AbortRchgSA/#8) is set as Visible and not required by default. The  combo box (Mode/#16) is a required field. My attempts have taken two  forms.
Form 1:
var f = this.getField("Mode").value;
if (f = SA)
{var g = this.getField("AbortRchgSA");
g.required = true;}
Form 2:
if (this.Field.Mode.value == SA)
this.getField(“AbortRchgSA”) = required;
else
this.removeField(“AbortRchgSA”);
Any and all help is welcome.

Answer 1

For the second script, rather than removing the field, you should hide it, since you may want it back. You're also using curly quotes, which will cause an error.
Try something like the following as the combo box's custom Validate script:
// Custom Validate script for combo box
(function () {
    var f = getField("AbortRchgSA");
    f.value = f.defaultValue;
    if (event.value === "SA") {
       f.display = display.visible;
       f.required = true;
    } else {
        f.display = display.hidden;
        f.required = false;