오른쪽키 방지

<script language=JavaScript1.1>
function right(e) {
if (navigator.appName == 'Netscape' &&
(e.which == 3 || e.which == 2))
return false;
else if (navigator.appName == 'Microsoft Internet Explorer' &&
(event.button == 2 || event.button == 3)) {
alert("오른쪽키 안됩니다");
return false;
}
return true;
}
document.onmousedown=right;
if (document.layers) window.captureEvents(Event.MOUSEDOWN);
window.onmousedown=right;
</script>