Forms: Forms for special script applications
The use of forms for applications other than collecting information, search functions or navigation does not affect the reachability or accessibility in the same manner. Such forms are often special script applications. For example, they are used for scaling the font size on the pages, varying CSS (Cascading Style Sheets) for a modified appearance or other preference settings.
By their nature these applications are not crucial for the use of the site or for accessing the information. Moreover, for many of these applications there are standard options in the browser which the visitor can use to set his preferences.
Do not confront the visitor with non-working applications
A rule of thumb for creating such applications: do not confront a visitor with an application that does not work if certain technologies are not supported by the browser. This can be achieved by…
- …providing additional support by means of server-side scripts.
The web developer must have access to server-side scripts. Furthermore this method will cost him more time than the following method. - …having forms for this application generated on the page by client-side scripts.
If a browser does not support scripts the application will not be displayed. Experience with server-side scripts is not required. - …changing the properties of HTML elements through object manipulation.
This solves the problem by turning the situation around. If the browser supports advanced functions, simple HTML – for instance, a list of textual links – is transformed into a form with a menu. If the browser does not support tge required script and DOM functions, the basic functionality will remain available as a list of textual links. Consequently, no alternative provisions for this type of navigation are needed.
Do not confront a visitor with a non-working form if optional technologies – such as CSS or client-side script – are not supported by the browser.
Guideline R-pd.13.6
Accessibility enhancements
Simple accessibility enhancements for forms, such as the label element and the tabindex attribute, can make it easier for visitors to click on form fields or tab through the application. See Input fields and labels and Forms and keyboard navigation.
Of course the benefits of these enhancements for visitors who are blind remain. However, some applications such as scaling font size, are not useful for blind visitors. Consequently, the question whether an accessibility enhancement requires attention depends on the application.
