title: Simplify the very long if statement in PHP
body: <pre><code>$gateway_site_id = $_POST['gateway_site_id'];
  $site_location = $_POST['site_location'];
  $city = $_POST['city'];
  $contact = $_POST['gateway_site_id'];
  $date_installed = $_POST['date_installed'];
  $care_of = $_POST['care_of']; 
  $notes = $_POST['notes'];
  $gateway_username = $_POST['gateway_username'];
  
  
  
  if(empty($gateway_username)){
      $gateway_username="N/A";
  }if(empty($notes)){
      $notes="N/A";
  }if(empty($care_of)){
      $care_of="N/A";
  }if(empty($date_installed)){
      $date_installed="N/A";
  }if(empty($city)){
      $city="N/A";
  }if(empty($site_location)){
      $site_location="N/A";
  }if(empty($gateway_site_id)){
      $gateway_site_id="N/A";
  }
  </code></pre>
  
  <p>When I submit my form, I just want to set empty fields with <code>N/A</code>.
  My code is working but  I think its too long, is there a way to simplify it?</p>