What would be a better to state the following:
var active = '-active';
if ($j('body').hasClass('faqs')) { $j('.faqs-support').toggleClass('faqs-support' + active); }
if ($j('body').hasClass('cameras')) { $j('.camera-support').toggleClass('camera-support' + active); }
if ($j('body').hasClass('manuals')) { $j('.manuals-support').toggleClass('manuals-support' + active); }
if ($j('body').hasClass('downloads')) { $j('.downloads-support').toggleClass('downloads-support' + active); }
How about:
$j.each(['faqs', 'cameras', 'manuals', 'downloads'], function(i, e){
if ($j('body').hasClass(e)) {
$j('.'+e+'-support').toggleClass(e+'-support-active');
}
});
$j('body') so it doesn't have to find elements by tag name a bunch of times, only to get the same result and throw things away.
var $body = $j('body');
var arr = ['faqs', 'cameras', 'manuals', 'downloads'];
$j.each(arr, function(index, item) {
if($body.hasClass(item)) $j('.' + item + '-support').toggleClass(item + '-support-active');
});
Is about how I would write that. Not much shorter or much more efficient, but clearer.
If that's the only class on the body, just grab the full className, and use it for the DOM selection and the .toggleClass():
var body_class = document.body.className + '-support';
$j('.' + body_class).toggleClass(body_class + '-active');
Just one change you'd need to make would be to change '.camera-support' to '.cameras-support'. (Adding the "s".)
if the body can only have one of those classes then you could do:
var cls = $j('body').attr('class');
if(cls)
$j('.'+cls+'-support').toggleClass(cls+'-support-active');
cls+'-support'+active to cls+'-support-active'