Fill select dropdown based on selected item

Question

I'm working on a rails app.

I have a dropdown with countries. Selecting a country would fill the city dropdown with the cities in that country.

I know how to do this server-side, but I'd like to do it client-side if possible. I've used the RJS helpers, but I've no experience with jQuery (not exactly even sure what it is) or the other selector javascript libraries.

Clarification: I'd like to do this entirely client-side. That is, send all the values in the initial page request. I'm not looking to call the server ajaxically, hit the database, then return those results. I'd like them loaded up with the page.

Answer 1

Creating a long list of elements with javascript will most likely perform worse on the client. Why would you prefer it?

Answer 2

Maybe this can help (a simple google search did it):

http://remysharp.com/2007/01/20/auto-populating-select-boxes-using-jquery-ajax/

Answer 3

I recommend you to use jQuery for this. But you need to take look documentation of jquery and then take a look jQuery ajax api

Answer 4

I used a combination of jQuery and the jQuery calculations plugin to get this working.