A form is made of elements that typically correspond to HTML form
input. Zend_Form_Element encapsulates single form elements, with the
following areas of responsibility:
-
validation (is submitted data valid?)
capturing of validation error codes and messages
filtering (how is the element escaped or normalized prior to validation and/or for output?)
rendering (how is the element displayed?)
metadata and attributes (what information further qualifies the element?)
The base class, Zend_Form_Element, has reasonable defaults
for many cases, but it is best to extend the class for commonly used
special purpose elements. Additionally, Zend Framework ships with a
number of standard XHTML elements; you can read about them in the Standard Elements
chapter.