title: Check if $_POST exists
body: <p>I'm trying to check whether a $_POST exists and if it does, print it inside another string, if not, don't print at all.</p>
  
  <p>something like this:</p>
  
  <pre><code>$fromPerson = '+from%3A'.$_POST['fromPerson'];
  
  function fromPerson() {
      if !($_POST['fromPerson']) {
          print ''
      } else {
          print $fromPerson
      };
  }
  
  $newString = fromPerson();
  </code></pre>
  
  <p>Any help would be great!</p>