PDF Forms in Adobe LiveCycle

I am making a form for the first time in Adobe Livecycle. I have a working version of the form using javascript here to demonstrate what I need it to do.

On the form, I have a drop down menu with a list of counties - when someone selects their county, I need an associated address to show up further down the form. How can I do this in a .pdf? What is it called?

I am pretty ignorant about this process, so if someone could even just give me the correct terms to search for, I’d be really grateful. Thanks!

Rather than type out the answer here, I’ll just point you to the help file that explains it.

Open help and search for the phrase:
To dynamically populate a second field after populating the first

Thank you! I appreciate it. Heh, obviously I have a lot of learning to do in the next few hours.

Also try the forums at Dynamic Drive, they have one of the best forums for question re: JavaScript, PHP, HTML, DHTML, etc