if (window.event)
document.captureEvents (Event.MOUSEUP);
function nocontextmenu () {
event.cancelBubble = true
event.returnValue = false;
return false;
}
function norightclick(e){
if (window.event) {
   if (e.which == 2 || e.which == 3)
   return false ;
}
else
   if (event.button == 2 || event.button == 3) {
    event.cancelBubble = true
    event.returnValue = false;
    return false;
   }
}
document.onmousedown = norightclick;