HTML Form

HTML Form is very useful to make some input. As the registration page, email page, etc. Typically, a website designer is always to complete construction of a form by modifying the control (such as checkboxes, radio buttons, etc.).

<form> . input elements . </form>

---

Issues:

The incremental display of documents being received from the network gives rise to certain problems with respect to forms. User agents should prevent forms from being submitted until all of the form's elements have been received.

The incremental display of documents raises some issues with respect to tabbing navigation. The heuristic of giving focus to the lowest valued tabindex in the document seems reasonable enough at first glance. However this implies having to wait until all of the document's text is received, since until then, the lowest valued tabindex may still change. If the user hits the tab key before then, it is reasonable for user agents to move the focus to the lowest currently available tabindex.

If forms are associated with client-side scripts, there is further potential for problems. For instance, a script handler for a given field may refer to a field that doesn't yet exist.

Future projects specification defines a set of elements and attributes powerful enough to fulfill the general need for producing forms. However there is still room for many possible improvements. For instance the following problems could be addressed in the future:

• The range of form field types is too limited in comparison with modern user interfaces. For instance there is no provision for tabular data entry, sliders or multiple page layouts.
• Servers cannot update the fields in a submitted form and instead have to send a complete HTML document causing screen flicker.
• These also cause problems for speech based browsers, making it difficult for the visually impaired to interact with HTML forms.

Another possible extension would be to add the usemap attribute to INPUT for use as client-side image map when "type=image". The AREA element corresponding to the location clicked would contribute the value to be passed to the server. To avoid the need to modify server scripts, it may be appropriate to extend AREA to provide x and y values for use with the INPUT element.