title: Shortcut for checking if all $_POST fields are filled in php
body: <p>I know that I can check if the superglobal $_POST is empty or not by using </p>
  
  <pre><code>empty / isset
  </code></pre>
  
  <p>However, I have many fields here. Is there any shortcut to check if all fields are filled? Instead of doing</p>
  
  <pre><code>if (!empty($_POST['a']) || !empty($_POST['b']) || !empty($_POST['c']) || !empty($_POST['d']).... ad nauseum)
  </code></pre>
  
  <p>Thanks in advance!</p>