How to scroll page elements with the keyboard?

Question

I basically want to achieve the same effect as in Google Reader: when you press "j", you are pushed down to the next article and when you press "k", you can go back up to the previous article. What is the simplest way of doing this?

Answer 1

Using onkeyup and use the keyCode to determine the key pressed: http://jsfiddle.net/pimvdb/gzRwN/1/.

document.body.onkeyup = function(e) {
    var code = e.keyCode;
    if(code === 74) { // key code for j
        window.scrollTo(document.body.scrollLeft,
                        document.body.scrollTop + 500);
    }
};