What FVOS Does
FVOS informs the user that they have left required form fields empty using a feature of Dynamic HTML. Empty fields and their text labels are rewritten to the page, while fields that were filled in properly are presevered as hidden fields. The fields can be rewritten an unlimited number of times, until the user fills out all required fields.
So What?
Yes, you have seen this before. Or at least you think you have. What makes this program special is that it is written in JavaScript. Since JavaScript is client-side, several problems caused by doing the exact same thing with a server side language are solved:
- Validation executes immediately - the user is not forced to wait for the data to be submitted, validated, then sent back.
- Excess Data Traffic is eliminated. This is important to a site owner if they pay for traffic.
- Server CPU cycles are saved. The server's load is reduced because execution happens client side.
- Did I mention the user does not have to wait for validation?
Features
Flexibility
Multiple fields can be grouped together, as in the case when 3 text fields are used to gather the 3 parts of a phone number. FVOS can be instructed to rewrite such a group of fields together if one or more fields are left empty. It also "remembers" the value of any field(s) in the group that was filled in by the user so that when the group is rewritten, the user doesn't have to enter the same info more than once.
Groups can also contain different field types, i.e. your form can have a set of radio buttons grouped together with a select menu and a textarea if that's what you want.
Compatibility
The program is backward and forward compatible.
-Browsers that do not support Dynamic HTML functionality can still run the program, but the validation they will execute is in the form of the old standby, JavaScript alerts.
-The (rewritten) HTML output is 100% XHTML 1.0 compliant, regardless of how you write the original form. The XHTML output does not affect older browsers because they use alerts for missing required fields.
The following browser/OS combinations have been tested and support FVOS's DHTML functionality: Internet Explorer 5.5 and 6.0, Netscape Navigator 6.2, Opera 7.1, and AOL 7.0 all on Windows OS, and MSIE 5.16 on Mac PowerPC to error-free results. Browsers that do not support its DHTML functionality (NN4.x) will perform validation using old fashioned JavaScript alerts.
Prettier Forms
Both form buttons and images are supported for the "Submit" and "Reset" form controls.