function arrowKeys(e) { switch(e.keyCode) { case 39: var prev = document.getElementById('prev'); if(prev) prev.click(); break; case 37: var next = document.getElementById('next'); if(next) next.click(); break; case 82: var random = document.getElementById('random'); if(random) random.click(); } } if(document.readyState == 'complete' || document.readyState == 'loaded') document.addEventListener('keydown', arrowKeys); else { if(/Chrome/i.test(navigator.userAgent)) window.addEventListener('load', function () { document.addEventListener('keydown', arrowKeys); }); else document.addEventListener('DOMContentLoaded', function () { document.addEventListener('keydown', arrowKeys); }); }