Using jQuery, how do I force a visitor to scroll to the bottom of a textarea to enable the submit button?

Question

I have a registration form which contains a read-only textarea. I want to require any visitor to scroll to the bottom of the textarea, which contains terms and conditions or

Answer 1

Something like this should work:

$('#terms').scroll(function () {
    if ($(this).scrollTop() == $(this)[0].scrollHeight - $(this).height()) {
        $('#register').removeAttr('disabled');
    }
});

Simply give terms an id, and set the register button to disabled in the html. I also made a little fiddle to show it working: http://jsfiddle.net/ETLZ8/