Acitve navigation item when selected submenu (no js)

Question

I am looking to find a way to highlight a navigation item when selecting submenu item. It has to be done in PHP. The menu is located is loaded as include on each page, dynamically. Also, i am not a programmer so please explain like you would for a beginner.

I have the following menu in include.php file:

    <?php
  function setActive($name){
    global $pageName;
    if ($pageName == $name){
      echo "class='active' ";
    }
  }
?>



<ul id="menu">
    
  <li ><a <?php setActive ('A')?> href="a.php">A</a></li>
  <li ><a <?php setActive ('B')?> href="a.php">B</a></li>
        <li>
            <a  href="#"  >C</a>
          
            <ul>
                <li><a href="D.php">D</a></li>
                <li><a href="E.php" >E</a></li>
            </ul>
        </li>
        <li>
</ul>

Each page has the following:

<?php
 $pageName ='D';

require "include.php";

?>

How can I make 'active' the main menu item C when either D or E are selected?

Thank you.

Answer 1

There are way better ways to do this, with a proper menu stucture, but using the system you have already got, you could do something like this:

 <?php
  function setActive($name) {
    global $pageName;
    if ($pageName == $name){
      echo "class='active' ";
    }
  }

function setMultiActive($array_of_names) {
  global $pageName;
  foreach ($array_of_names as $name) {
    if ($pageName == $name) {
      echo "class='active'";
      break;
    }
  }
?>



<ul id="menu">
    
  <li ><a <?php setActive ('A')?> href="a.php">A</a></li>
  <li ><a <?php setActive ('B')?> href="a.php">B</a></li>
        <li>
            <a  href="#" <?php setMultiActive(['D', 'E']) ?>>C</a>
          
            <ul>
                <li><a href="D.php">D</a></li>
                <li><a href="E.php" >E</a></li>
            </ul>
        </li>
        <li>
</ul>