Question

I am wanting to find the href in the series class and then replace the [PAGEURL] with the same link. I also need this to repeat the function for every .details class on the page.

Here is the JavaScript that I am using –

$(function() {
  var links = $('.details'),
    matchExp = /\[PAGEURL\]/,
    currentURL = $('.series').attr('href');

  links.each(function() {
    var currentHREF = $(this).attr('href');
    if (currentHREF.match(matchExp)) {
        $(this).attr('href',currentHREF.replace(matchExp,currentURL));
    }
  });
});

And here is the HTML

<div class="details">
  <div class="series">
    <a href="MyLink.php">text</a>
  </div>
  <fb:comments-count href=[PAGEURL]></fb:comments-count>
</div>

Answer 1

I don’t think that you need to use regular expressions in this instance.
jQuery provides you with enough tools to get the job done.

Here is how I would accomplish a “search and replace” function on some link placeholders:

Given the following HTML –

<div class="details">
  <div class="series"><a href="my_cool_page.php">text</a></div>
  <fb:comments-count href="[PAGEURL]"></fb:comments-count>
</div>

<div class="details">
  <div class="series"><a href="awseome_content.php">text</a></div>
  <fb:comments-count href="[PAGEURL]"></fb:comments-count>
</div>

<div class="details">
  <div class="series"><a href="interesting_stuff.php">text</a></div>
  <fb:comments-count href="[PAGEURL]"></fb:comments-count>
</div>

This jQuery would do the trick –

$(function(){
    // this grabs all the div elements with the class "details"
    $("div.details").each(function(index,elem){

      // within each details <div>, we look for an <a> element, and
      // we save its href value in currentURL
      var currentURL = $(this).find('div.series > a').attr('href');

      // again within the details <div>, we search for any element who's href
      // property contains [PAGEURL] and replace is with the value
      // we got from the series <a> tag.
      $(this).find('*[href*="[PAGEURL]"]').attr('href',currentURL);
    });
});​

The final desired result should look like this –

<div class="details">
  <div class="series"><a href="my_cool_page.php">text</a></div>
  <fb:comments-count href="my_cool_page.php"></fb:comments-count>
</div>

<div class="details">
  <div class="series"><a href="awseome_content.php">text</a></div>
  <fb:comments-count href="awseome_content.php"></fb:comments-count>
</div>

<div class="details">
  <div class="series"><a href="interesting_stuff.php">text</a></div>
  <fb:comments-count href="interesting_stuff.php"></fb:comments-count>
</div>

jsFiddle demo

I made one change to the actual HTML from your question. The value of the href property (and any property for that matter) should always be surrounded with quotes.

<fb:comments-count href=“[PAGEURL]“></fb:comments-count>