Trying to make a Controller to handle custom exporting of data.
Created a file CompetitionExport_Controller.php and placed into code directory.

class CompetitionExport_Controller extends Controller
{
	function index() {
		return $this->renderWith('CompetitionReport_Export');
	}
}

In the config file, I have defined this rule:

Director::addRules(50, array(
	'compexp/$Action/$ID' => 'CompetitionExport_Controller'
));

Yet when I go to the URL http://mysite/compexp/index/621 I receive the following error:
Fatal error: Class 'CompetitionExport_Controller' not found in /sapphire/core/control/Director.php on line 274

Can anyone provide me with what I'm doing wrong?
Everything looks fine from what I can tell based upon this page: http://doc.silverstripe.org/controller

This is with SS 2.3.2.

You need to add ?flush=1 or ?flush=all to the end of the URL, the class hasn't loaded yet...

Also the controller should be in a file named "CompetitionExport.php" not "CompetitionExport_Controller.php".

Cheers,
Sean

Oh man - forgot about the name of the file. That was my problem.

Thanks for the answer Sean.