Forms are the primary means through which applications accept user input. They are used for a wide variety of purposes, such as gathering user information, performing searches, and placing orders for products and services. But whatever the purpose of a specific form, they all share several common features:
A form is composed of input text fields, menus, checkboxes, radio buttons, push buttons, and possibly other custom control types such as sliders, dials, calendars, and even images.
A form submits data to be processed further, often by a server-side script.
Many forms validate their data before submitting it for processing to ensure that all necessary information has been entered properly.
A form may be limited to one page (screen) or be spread across several pages, depending on its length and appropriate user considerations.
ActionScript provides text fields as well as standard UI components for creating the elements of a form, but it does not provide a native Form class to manage the user input process or the form as a whole. However, this chapter includes recipes that enable you to create and utilize forms effectively in your Flash movies. These recipes extend the functionality of existing UI components, define a Form class, and define a MultiPageForm class. You should place all of this code in a Form.as file and save it to your Flash Include directory so that you can reuse the code easily in your applications.