var isnn,isie
if(navigator.appName=='Microsoft Internet Explorer')  // check the browser
{ isie=true }


if(navigator.appName=='Netscape')
{ isnn=true }


function right(e)  // to trap right click button 
{
        if (isnn && (e.which == 3 || e.which == 2 ))
 return false;
        else if (isie && (event.button == 2 || event.button == 3)) 
        {
 alert("Sorry, you do not have permission to right click on this page.");
 return false;
        }
 return true;
}


function key(k) 
{
        if(isie) {
 if(event.keyCode==17 || event.keyCode==18 || event.keyCode==93) {
 alert("Sorry, you do not have permission to press this key.") 
 return false;
 } 
        }


        if(isnn){
 alert("Sorry, you do not have permission to press this key.") 
 return false; } 
}


if (document.layers) window.captureEvents(Event.KEYPRESS); 
if (document.layers) window.captureEvents(Event.MOUSEDOWN);
if (document.layers) window.captureEvents(Event.MOUSEUP);
document.onkeydown=key; 
document.onmousedown=right;
document.onmouseup=right;
window.document.layers=right;