How to use preg_replace for replacing href attribute values with a Javascript function name in a PHP string

I have the following HTML code as a string in a PHP variable:

<ul class="pagination">
<li class="active">
<a href="http://localhost:8080/admin/locationlist?filter_name=emirate&filter_value=dubai&page=1">
1</a>
</li>
<li >
<a href="http://localhost:8080/admin/locationlist?filter_name=emirate&filter_value=dubai&page=2">
2</a>
</li>
<li >
<a href="http://localhost:8080/admin/locationlist?filter_name=emirate&filter_value=dubai&page=3">
3</a>
</li>
<li>
<a href="http://localhost:8080/admin/locationlist?filter_name=emirate&filter_value=dubai&page=4" aria-label="Next">
<span aria-hidden="true">Next</span>
</a>
</li>
<li>
<a href="http://localhost:8080/admin/locationlist?filter_name=emirate&filter_value=dubai&page=60" aria-label="Last">
<span aria-hidden="true">Last</span>
</a>
</li>
</ul>

I would like to replace the URL from the HTML tags and instead replace with the following text:

javascript:loadItems(<pagenumber>);

Please note that the query parameters filter_name=emirate&filter_value=dubai can change based on user search. For example: filter_name=location&filter_value=Samha

The final replaced HTML string should be as follows:

<ul class="pagination">
<li class="active">
<a href="javascript:loadLocationList(1);">
1</a>
</li>
<li >
<a href="javascript:loadLocationList(2);">
2</a>
</li>
<li >
<a href="javascript:loadLocationList(3);">
3</a>
</li>
<li>
<a href="javascript:loadLocationList(4);" aria-label="Next">
<span aria-hidden="true">Next</span>
</a>
</li>
<li>
<a href="javascript:loadLocationList(60);" aria-label="Last">
<span aria-hidden="true">Last</span>
</a>
</li>
</ul>

How to do this replacement?

EDIT:

I tried this:

$pager_links = str_replace("http://localhost:8080/admin/locationlist?filter_name=&filter_value=&page=", "javascript:loadLocationList();", $pager_links);

$pattern = '/\);([0-9]+)/i';
$replacement = '$1);';
$pager_links = preg_replace($pattern, $replacement, $pager_links);

When there is some content inside filter_name and filter_value parameters, I am not able to replace it properly.

It is never a Good Idea to use regex to parse HTML.

I suggest you change it to insert a simple piece of JS in the document

Your loadItems became loadLocationList, so I kept the latter

window.addEventListener('load', () => {
  const loadLocationList = page => console.log(page);
  
  document.querySelector('ul.pagination') // Targeting the pagination <ul> specifically
    .addEventListener('click', (e) => {
      // Find the closest <a> element to e.target
      const link = e.target.closest('a');

      // If no <a> is found, ignore the event
      if (!link) return;

      // Prevent default link behavior
      e.preventDefault();

      // Get the href attribute
      const href = link.getAttribute('href');

      try {
        // Parse the href using the URL interface
        const url = new URL(href, window.location.origin); // Use origin as base for relative URLs
        const page = url.searchParams.get('page');

        // If page parameter exists, call loadItems with the page number
        if (page !== null) {
          loadLocationList(Number(page));
        }
      } catch (e) {
        // Ignore invalid URLs or non-URL hrefs 
        return;
      }
    });
});

<ul class="pagination">
  <li class="active">
    <a href="http://localhost:8080/admin/locationlist?filter_name=emirate&filter_value=dubai&page=1">1</a>
  </li>
  <li>
    <a href="http://localhost:8080/admin/locationlist?filter_name=emirate&filter_value=dubai&page=2">2</a>
  </li>
  <li>
    <a href="http://localhost:8080/admin/locationlist?filter_name=emirate&filter_value=dubai&page=3">3</a>
  </li>
  <li>
    <a href="http://localhost:8080/admin/locationlist?filter_name=emirate&filter_value=dubai&page=4" aria-label="Next">
<span aria-hidden="true">Next</span>
</a>
  </li>
  <li>
    <a href="http://localhost:8080/admin/locationlist?filter_name=emirate&filter_value=dubai&page=60" aria-label="Last">
<span aria-hidden="true">Last</span>
</a>
  </li>
</ul>

If you MUST do it in PHP, then give this a try, a combination of dom parsing and url parsing - not tested

function transformPaginationUrls($html) {
  $doc = new DOMDocument();
  @$doc->loadHTML($html, LIBXML_HTML_NOIMPLIED | LIBXML_HTML_NODEFDTD);
  
  $links = $doc->getElementsByTagName('a');
  
  foreach ($links as $link) {
    $href = $link->getAttribute('href');
   
    // Parse the URL
    $parsedUrl = parse_url($href);
        
    // Check if the URL has a query string
    if (isset($parsedUrl['query'])) {
      // Parse query string into an array
      parse_str($parsedUrl['query'], $queryParams);
          
      // Check if the page parameter exists
      if (isset($queryParams['page'])) {
        $pageNumber = $queryParams['page'];
        // Replace href with JavaScript call
        $link->setAttribute('href', "javascript:loadLocationList({$pageNumber});");
      }
    }
  }
  return $doc->saveHTML();
}



    // Calling the method
$urlFragment  = '<ul>.....</ul>';
$replacedHref = transformPaginationUrls($urlFragment);