I have a project where people can book places on events. There are dozens of events. I have been requested to generate a report listing attendees so they can be checked in at the door. Because there are so many events, I would like to add an "Attendees Report" button to the editform for each event. I have the button, and it works.

BUT... instead of outputting the data in a CSV, I get the (correct) data displaying in the CMS as if it was being echoed.

Here is my function

//***********************************************
	public function getCustomersForEvent($data, $form){
//***********************************************

		$attendees = CustomerOrderLine::get()->filter(array("EventID" => $data["ID"]));

		if(!$attendees){
			return false;
		}

		$fileName = "report.csv";

		$separator = ",";
		$csvColumns = array("ID", "Description", "Customer");

		$fileData = "";

		foreach($attendees as $row){
			$fileData .= $row->Event()->EventName . $separator;
			$fileData .= $row->CustomerOrder()->Customer()->FirstName . " " . $row->CustomerOrder()->Customer()->Surname . "\n";
		}

		return SS_HTTPRequest::send_file($fileData, $fileName, 'text/csv');
	}

I have had a look at this http://www.silverstripe.org/community/forums/general-questions/show/15325 but the data echoed to the CMS anyway.

Can someone please tell me what I am doing wrong? As I said, the data is fine, but I'm not getting the CSV Open or Save dialog.

In the end, I wrote everything to a file in the assets folder and returned a sprintf with a link to the file. But really, it looks kind of yuk, so if anyone has a better suggestion, I'd be really happy to hear it.

I've sometimes made it easy for myself by adding a link to the editform, in this case probably someting like

<a href="/showresults/csv?event=4" target="blank">Export csv</a> 

Then create a CSVEventController, with a function csv() that returns the details, set the proper routing in yml, and you're on your way :)

A lot easier would be to create a modeladmin for the events, make it filterable on event title, and use the default export to CSV button. If you don't want people to edit events from there, make sure it's readonly...