Change param type for course_code

download.php

@@ -29,7 +29,7 @@ require_once($CFG->libdir.'/csvlib.class.php');
 
 $PAGE->set_url('/local/hshexport/download.php');
 
-$course_code = optional_param('code', null, PARAM_ALPHANUMEXT);
+$course_code = optional_param('code', null, PARAM_TEXT);
 $courseid = required_param('id', PARAM_INT);
 $coursecontextid = required_param('context', PARAM_INT);
 $roles = required_param('roles', PARAM_TEXT);