Question

When printing invoices from Magento I need the orders tracking number (if available) to be printed on the invoice.

Any ideas how to do this?

Answer 1

Actualy Tracking Number is a part of shipment, not invoices. But if you want to check whether the tracking number is available you can use this :

$shipments = $order->getShipmentsCollection();
if ($shipments) {
   foreach ($shipments as $shipment) {
      foreach ($shipment->getAllTracks() as $track) {
         $trackingNumbers[] = $track->getTrackNumber();
      }
   }
}

It will return the tracking number in array (if you have more than 1 shipment). Hope this helps.