I've just finished an iCalendar vCard parser for PHP. It's done almost completely with a 'natural' simplexml-like interface, so it should (hopefully) be just as easy to parse, and also modify iCalendar / vCard objects (ics/vcf files).

To install using pear, run the following:

    pear channel-discover pear.sabredav.org
    pear install sabredav/Sabre_VObject-alpha

Or download from pear.sabredav.org.

For testing, I used this iCalendar file: icalendartest.ics.

To load in an object, you use the Reader class:

    // Link to the correct path if you manually dowloaded the package
    include 'Sabre/VObject/includes.php';
     
    // Reading an object
    $calendar = Sabre_VObject_Reader::read(file_get_contents('icalendartest.ics'));

iCalendar objects consist of components (VEVENT, VTODO, VTIMEZONE, etc), properties (SUMMARY, DESCRIPTION, DTSTART, etc) and parameters, which are to properties what attributes are to elements in XML. To show a listing of all events in a calendar, this snippet would work:

    echo "There are ", count($calendar->vevent), " events in this calendar\n";
     
    // Looping through events
    foreach($calendar->vevent as $event) {
     
    echo (string)$event->dtstart, ": ", $event->summary, "\n";
     
    }

You can easily modify properties:

    $calendar->vevent[0]->description = "It's a birthday party";

Creating new objects uses the following syntax:

    $todo = new Sabre_VObject_Component('vtodo');
    $todo->summary = 'Take out the dog';
    $calendar->add($todo);

And to turn your newly modified calendar back into an ics file:

    file_put_contents('output.ics', $calendar->serialize());

Lastly, parameters are accessible through array-syntax:

    echo (string)$calendar->vevent[0]->dtstart['tzid'], "\n";

I had fun building this, I hope it's useful to you as well. It's 100% unittested, but bugs might still appear due to the complex nature of API. Use at your own risk :). This library will be part of the SabreDAV project, which is also where you can go for the source, report bugs or make suggestions.