[ic] Client side javascript and the [button] tag.

[Ethan E. Rowe]

Peter wrote:

> Cameron G wrote:
>
>> Hi guys, I'm sitting here pondering the best way to achieve this 
>> task, and I
>> figured I'd throw it amongst a few other heads and see if anything 
>> comes up.
>> Basically, on my checkout page, I want a checkbox they must tick in 
>> order
>> for the submission to succeed. Of course, I can check it within the 
>> order
>> profile, but that requires the page to be reloaded - so I was thinking
>> client side JS. The only problem with this that I can see is that the 
>> button
>> tag appears to only have a confirm option, not an onClick. Am I 
>> wasting my
>> time by pondering this, or is there an easy way around it? 
>
>
> Use OnSubmit for the <Form> tag.  Keep in mind that disabling 
> javascript will work around the requirement for checking the box.
>
Also keep in mind that there are still plenty of users out there using 
non-javascript-supporting browsers such as Lynx.  This is an issue that 
comes up when you worry about accessible design (though the 
accessibility guidelines tend to focus more on how you use HTML and CSS 
stylistically); my employer (National Braille Press, Inc) primarily 
serves the braille-reading community, and I've consequently learned that 
there are a lot of visually-impaired computer users out there who prefer 
the command line interface to the visually-oriented GUIs of Windows, 
Mac, etc.  Such users will employ browsers such as Lynx, and it's 
extremely frustrating for that community when sites are reliant on 
Javascript.  Just yesterday I encountered a site that requires users to 
register in order to access any significant features, and the 
registration form uses an <a href="...">...</a> tag rather than a 
standard submit button; the anchor tag's HREF points to a javascript 
function that authenticates and submits the form.  Were the javascript 
function called via the OnSubmit event of the <form>, that would be one 
thing (Lynx would be free to ignore the OnSubmit); however, in this 
case, the link just doesn't work in Lynx and consequently, the site is 
not usable for a particular user community.

This is getting pretty picky, but perhaps it's of interest to you.  Web 
design frequently gets into the sticky area of backwards compatibility 
and it doesn't always make sense for a particular organization to try to 
support older browsers.  However, considering the flexibility 
Interchange gives you in form validation and error-reporting, the safest 
choice for such things is to avoid javascript for critical functions 
(unless you can absolutely guarantee that your users will run a certain 
type of browser), and failing that, always back it up with server-side 
validation/processing.

-Ethan Rowe
Interchange site: www.nbp.org (primarily designed by End Point Corp 
www.endpoint.com)