If you want this to happen entirely on the client side (in the browser), without a request to the server, then this is a JavaScript question and indeed off-topic for the Monastery, but I would encourage you to continue your research into jQuery, as that is probably what I would use.

If this is an HTML form that you want to submit to a CGI script on the server, or perhaps a dynamic XMLHttpRequest that exchanges data with the server in a format like JSON, then the server side could certainly handle this in Perl. However, because there are a lot of different ways to do this, you haven't given enough information to go on - please see How do I post a question effectively? and especially Short, Self-Contained, Correct Example.