kieranbarnes Independent PHP, WordPress & CubeCart Programmer

iCalendar Generation

One of my clients requested that the CRM applicationI wrote should interact with Outlook Calender.
For example, when adding a "Next Call Date" on the web based CRM application, the user's calendar is updated in Outlook so they are reminded even when not using the CRM application.

It should work for any VCalendar aware application, like Thunderbird & Lightning or Sunbird.
Heres how I did it, Create a file called make_calender.php

// Define the file as an iCalendar file
header("Content-Type: text/Calendar");

// Give the file a name and force download
header("Content-Disposition: inline; filename=calendar.ics");

// Header of ics file
echo "BEGIN:VCALENDAR\n";
echo "VERSION:2.0\n";
echo "PRODID:PHP\n";
echo "METHOD:REQUEST\n";
echo "BEGIN:VEVENT\n";
echo "SUMMARY: PUT SUMMARY DETAILS HERE \n";
echo "DESCRIPTION: PUT DESCRIPTION DETAILS HERE";
echo "DTSTART:".DATE HERE."T090000\n";
echo "DTEND:".DATE HERE."T090000\n";
echo "UID: ".rand()."\n";
echo "SEQUENCE:0\n";
echo "DTSTAMP:".date('Ymd').'T'.date('His')."\n";
echo "BEGIN:VALARM\n";
echo "TRIGGER:-PT30M\n";
echo "REPEAT:1\n";
echo "ACTION:DISPLAY\n";
echo "END:VALARM\n";
echo "END:VEVENT\n";
echo "END:VCALENDAR\n";

You will need to populate the code with the following, presumably from a database record just before the above code.

Summary
echo "SUMMARY: PUT SUMMARY DETAILS HERE \n";

Description
echo "DESCRIPTION: PUT DESCRIPTION DETAILS HERE";

Date & Time
echo "DTSTART:".DATE HERE."T090000\n";
echo "DTEND:".DATE HERE."T090000\n";

The code also produces a trigger, in Outlook terms, a reminder.
It will "alarm", in Outlook terms pop up a window, 30 minutes before the event.
This can be seen as

echo "BEGIN:VALARM\n";
echo "TRIGGER:-PT30M\n";
echo "REPEAT:1\n";
echo "ACTION:DISPLAY\n";
echo "END:VALARM\n";

This code will generate an ICS file that the user will be prompted to Open. Once opened Outlook will save the event.

Its upto you how you call it.

Further reading

• Wikipedia's article
• IMC's original article

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