Form framework for dynaimcally adding, altering fields

I have several forms on my website in which fields are dynamically created or altered based on what is altered in previous fields? Is there a good framework for doing this easily开发者_StackOverflow社区?

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Kohana offers an Object Oriented approach to form generation and validation with their Formo module. The official Formo documentation can be found online at http://www.avanthill.com/formo_manual/

The compliment this server-side logic, jQuery (Javascript Framework) comes with a great Validation Plugin that is in wide-spread use all over the web. It too has a very simple and straight forward application.