csrf_exclude_uris not work

$config['csrf_protection'] = true;
$config['csrf_token_name'] = 'csrf_token_test';
$config['csrf_cookie_name'] = 'csrf_cookie_test';
$config['csrf_expire'] = 7200;
$config['csrf_regenerate'] = TRUE;
$config['csrf_exclude_uris'] = array('/assistant_dashboard/upload.html');

I upload file to '/assistant_dashboard/upload.html' but the 'csrf_exclude_uris' not work.
Please show me how to do?