title: How do I read values (PHP defined constants) from wp-config.php?
body: <p>I need to get username, password etc from the <code>wp-config</code> file to connect to a custom PDO database.</p>
  
  <p>Currently I have another file where I have this info, but I would like to only use the <code>wp-config</code>.</p>
  
  <p>So how can I read the different properties of <code>wp-config</code>?</p>