<html>
<head>
<script type="text/javascript">
function lolEvent(event)
{
event.keyCode == 13 ? alert("lol") : alert("notlol");
}
</script>
</head>
<body>
<form>
Press enter to make me lol:
<input type="text" onkeyPress="lolEvent(event)">
</form>
</body>
</html>