As mentioned in my previous post, I’ve been finishing up a facebook application, My Sites. Now that it’s done, I thought I’d post a few tips on how to add profile boxes to your facebook application, since I found it maddeningly complicated.

For the non-facebook-savy, a profile box is a small box that applications can add to your profile’s “wall” or “boxes” tabs. They’re meant to provide a quick glimpse of what’s happening with the application.

I’m assuming that you keep a database of Facebook users, and you want to display something about them in the profile box.

The basic code for adding a profile box is below, annotated with copious comments. This is in PHP code, you can do it in other languages, but it’s what I use. Pop this code into a daily cron for example, and you’re good to go.

<?php
// This code connects to the facebook API.
@require_once 'facebook-platform/php/facebook.php';
$appapikey = 'facebook app api key';
$appsecret = 'facebook app api secret';
$facebook = new Facebook($appapikey, $appsecret);

// This code connects to your own database.
$BASEURL = "http://example.com/path/to/facebook/app";
$connection = @mysql_connect("server","username","password");
if(!$connection)die("Can't connect to the database at this time.");
$res = @mysql_select_db("database");
if(!$res)die("Site database doesn't seem to exist.");

// This code cycles through each user in the database
$sql="SELECT * FROM users";
$data=@mysql_query($sql);
while($user=mysql_fetch_assoc($data)) {
     // You can, of course, query your database to build these strings
     $WideBox = "Whatever you want a profile box on the 'boxes' tab to say.";
     $MobileBox = "Whatever you want a profile box accessed by a mobile device to say.";
     $NarrowBox = "Whatever you want a profile box on the 'wall' tab to say.";

     // This is the API call, it sets the user's profile box content:
     $facebook->api_client->profile_setFBML(
          NULL,        // This is the markup, set to NULL for 'FBML'
          $user['id'],  // ID number of the user whose profile box you want to set
          $WideBox,    // Wide box content for 'boxes' tab
          NULL,        // Deprecated, should always be NULL
          $MobileBox,  // Box content for mobile devices
          $NarrowBox   // Narrow box content for 'wall' tab
     );
}
// Clean up the connection
@mysql_close($connection);
?>