<script type="text/javascript">  
window.addEventListener("message", function(event) {    
  if(event.data.type === 'hsFormCallback' && 
     event.data.eventName === 'onFormSubmitted' && 
     event.data.id === 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx'
    ) 
{    // This block pushes an event to the dataLayer if the above is TRUE      
window.dataLayer.push({        
  'event': 'form-submission-event-name',        
  'hs-form-guid': event.data.id,      });      
  console.log("HubSpot Form Submitted :)");    }  });
</script>
HubSpot Form Event Listener
