php dom replacedChild, save as html and continue parsing - php

Question

I created a php parser for editing the html which is created by a CMS. The first thing I do is parse a custom tag for adding modules.
After that things like links, images etc. are if needed updated, changed or w/e. This all works.
Now I noticed that when a custom tag is replaced with the html the module generated this html is NOT processed by the rest of the actions.
For example; all links with a href of /pagelink-001 are replaced with the actual link of the current page. This works for the initial loaded html, not the replaced tag. Below I have a short version of the code. I tried saving it with saveHtml() and load it with loadHtml() and things like that.
I'm guessing this is because $doc with the loaded html is not updated as such.
My code:
$html = 'Link1<customtag></customtag>';
// Load the html (all other settings are not shown to keep it simple. Can be added if this is important)
$doc->loadHTML($html);
// Replace custom tag
foreach($xpath->query('//customtag') as $module)
{
// Create fragment
$return = $doc->createDocumentFragment();
// Check the kind of module
switch($module)
{
case 'news':
$html = $this->ZendActionHelperThatReturnsHtml;
// <div class="news">Link2</div>
break;
}
// Fill fragment
$return->appendXML($html);
// Replace tag with html
$module->parentNode->replaceChild($return, $module);
}
foreach($doc->getElementsByTagName('a') as $link)
{
// Replace the the /pagelink with a correct link
}
In this example Link1 href is replaced with the correct value, however Link2 is not. Link2 does correctly appear as a link and all that works fine.
Any directions of how I can update the $doc with the new html or if that is indeed the problem would be awesome. Or please tell me if I'm completely wrong (and where to look)!
Thanks in advance!!

Answer 1

It seemed that I was right and the returned string was a string and not html. I discovered in my code the innerHtml function from #Keyvan that I implemented at some point. This resulted in my function being this:
// Start with the modules, so all that content can be fixed as well
foreach($xpath->query('//customtag') as $module)
{
// Create fragment
$fragment = $doc->createDocumentFragment();
// Check the kind of module
switch($module)
{
case 'news':
$html = htmlspecialchars_decode($this->ZendActionHelperThatReturnsHtml); // Note htmlspecialchars_decode!
break;
}
// Set contents as innerHtml instead of string
$module->innerHTML = $html;
// Append child
$fragment->appendChild($module->childNodes->item(0));
// Replace tag with html
$module->parentNode->replaceChild($fragment, $module);
}