Talk:lib/formslib.php Usage
From MoodleDocs
The sample code on this page refers to $fromform:
} else if ($fromform = $mform->get_data()) {
What is $fromform and where is it defined?
Answer: It is defined inside the exact IF you quoted ("$fromform = $mform->get_data()") and it holds all the form's data from the form's page (in to which, the user just entered her/his preferences) Now, it is your responsibility to save it into the $DB