How to observe more fields with AJAX helper

The observe_field AJAX helper allows to observe one field; if there is a change, it calls the specified method on the server side. It is possible to attach one value for the call.

This is enough if we have one text box search for searching over multiple columns or for a full-text search.

For a more complicated filtering functionality with more fields there are two main problems with the observe_field helper:

• how to specify more parameter values in the observe_field helper.
• it is necessary to write a observe_field call for each field.

http://www.valibuk.net/2006/08/how-to-observe-more-fields-with-ajax-helper/