title: adding newer version of PHP to XAMPP versus upgrading to newer version of PHP
body: <p>In my development environment, on Windows, I'm running XAMPP with PHP 5.4.4.  All of the projects in my htdocs folder are compatible with PHP 5.4.4.  Presently, only one of these projects needs to be refactored to work on PHP 7.3.4.</p>
  
  <p>This <a href="https://stackoverflow.com/questions/2154762/upgrading-php-in-xampp-for-windows/">post</a> describes how to upgrade to a newer version of PHP; however, I don't want to replace the 5.4.4 version that's already installed.  Instead, I want to add the 7.3.4 version so it's possible to choose which PHP version to run for each project.</p>
  
  <p>This <a href="https://themanish.com/run-multiple-version-of-php-in-xampp-windows-without-installing-multiple-xampp/" rel="nofollow noreferrer">post</a> describes how to install an older version of PHP alongside a newer version and how to run multiple versions of PHP on a single installation of XAMPP.  This is closer to what I want to achieve.  Instead of installing an older PHP version, I'd be installing a newer one.  Are there any reasons that the base PHP version that's installed should be the newest version?</p>
  
  <p><strong>Edit:</strong> I would like to set up my environment so the different PHP versions run on different ports, as described by the second post listed above.  In other words, I don't want to modify Apache's <code>httpd.config</code> file each time the PHP version is to be switched.</p>