Question

$(document).ready(function(){
  $("#menu ul").children('li').each(function(){
    var href = $(this).find('a').attr('href');
    var wpl = window.location.pathname;
    if( href.indexOf(wpl) != -1 ){
      if( wpl.indexOf( "category" ) != -1){
        $("#products").attr('id','prodon');
      }
      if( wpl.indexOf( "news" ) != -1){
        $("#news").attr('id','newson');
      }
      if( wpl.indexOf( "wheretobuy" ) != -1){
        $("#WTB").attr('id','WTBon');
      }....

It goes on a little longer, different buttons.
I’ve only done it this way because each button is an image so they’re all unique. This is a snippet of the HTML:

<li><a href="/news/index" id="news"></a></li>
<li>
  <a href="/site/wheretobuy" id="WTB"></a>
  <ul>
    <?php echo '<li>'.CHtml::link(CHtml::encode("Showrooms"), array('/showroom/index')).'</li>'; ?>
    <?php echo '<li>'.CHtml::link(CHtml::encode("Dealers"), array('/dealers/index')).'</li>'; ?>
    <?php echo '<li>'.CHtml::link(CHtml::encode("Hypermarket and Merchants"), array('/hyper/index')).'</li>'; ?>
  </ul>
</li>

So the parent nodes are all fine. Also, if a child’s URL contains the parent’s URL (i.e. category/cat), it shows the active button. I want to know how to apply a parent;s active img if one of its children is the URL, but not the same wording. I could do a bunch of more IFs but I think there’s an easier way.

EDited…. again

  if( wpl.indexOf( "wheretobuy" ) != -1 || $('#menu ul').find('.WTBon').parent().closest('li').indexOf( "wheretobuy" ) != -1 ) { 

    $('.WTB').addClass('WTBon');

}

So what I’m trying to check is if the parent of the node has wheretobuy in the URL

Answer 1

Try this:

instead adding ids add as class name.

$('#menu ul').find('.idon').parent()
             .closest('li').addClass('.idon'); // <--id like //newson//

updates for latest one:

if($('#menu li a[href*="wheretobuy"]').length){
   $('#menu a[href*="wheretobuy"]').parent('li').addClass('WTBon');
}

Note:

Using same ids for multiple elems on a single page is discouraged. Its not a good practice.

This applies in your case too because you have applied it by making the active one as id, You can use it as a class instead.