PHP prevent stripping spaces in only some situations

Question

Im trying to build an iCal feed in PHP ... I've taken some instruction from tutorials and have the following code;

public function getEventsICalObject()
{
   $events = TechEvents::all();
   define('ICAL_FORMAT', 'Ymd\THis\Z');

   $icalObject = "BEGIN:VCALENDAR
   VERSION:2.0
   METHOD:PUBLISH
   PRODID:-//Testing Calendar//Tech Events//EN\n";
  
   // loop over events
   foreach ($events as $event) {
       $icalObject .=
       "BEGIN:VEVENT
       DTSTART:" . date(ICAL_FORMAT, strtotime($event->starts)) . "
       DTEND:" . date(ICAL_FORMAT, strtotime($event->ends)) . "
       DTSTAMP:" . date(ICAL_FORMAT, strtotime($event->created_at)) . "
       SUMMARY:$event->summary
       UID:$event->uid
       STATUS:" . strtoupper($event->status) . "
       LAST-MODIFIED:" . date(ICAL_FORMAT, strtotime($event->updated_at)) . "
       LOCATION:$event->location
       END:VEVENT\n";
   }

   // close calendar
   $icalObject .= "END:VCALENDAR";

   // Set the headers
   header('Content-type: text/calendar; charset=utf-8');
   header('Content-Disposition: attachment; filename="cal.ics"');
  
   $icalObject = str_replace(' ', '', $icalObject);

   echo $icalObject;
}

This works great and outputs perfect except for one thing, at the bottom of the function it uses str_replace to strip spaces to make the output validate ... The problem is if the $event->summary or $event->location has any spaces in it, it strips them out too making the whole thing pointless.

Is there any way to prevent these from being stripped?

Answer 1

Assuming it's the start of the lines that you want to clean up, use following code:

$icalObject = preg_replace("/([\n\r]+)[ ]+/s","$1", $icalObject);

this will remove your spaces from the line beginnings.