<!--
//JavaScript verbergen voor oude browsers
     
if ((window.name !="Wiskunde_online")&&(window.name !="Grafieken_online")) {window.location="index.htm";}
//Disable right mouse click Script

var isNS = (navigator.appName == "Netscape") ? 1 : 0; var volgorde = 0; var ctrlKeyDown = false; var altKeyDown = false;

if(isNS)
{
 document.captureEvents(Event.MOUSEDOWN);
 document.captureEvents(Event.MOUSEUP);
 document.captureEvents(Event.KEYDOWN);
 document.captureEvents(Event.KEYPRESS);
 document.captureEvents(Event.KEYUP);
}

function mischandler()
{
 return false;
}

function mousehandler(e)
{
 var myevent = (isNS) ? e : event;
 var eventbutton = (isNS) ? myevent.which : myevent.button;
 if((eventbutton==2)||(eventbutton==3)) {return false; }
}

function keyDownhandler(e)
{
 var myevent = (isNS) ? e : window.event; 
 
 if(ctrlKeyDown == true && myevent.keyCode == 82){myevent.keyCode = null; return false}; //CTRL + R reload
 
 if(myevent.ctrlKey)
 {
  ctrlKeyDown = true; if(isNS){return false;}else{myevent.cancelBubble=true; return false; }; 
 }
 else if(myevent.altKey)
 {
  altKeyDown = true;
 } 
 else
 {
  return true;
 }
}

/*function keyPresshandler(e)
{
 var myevent = (isNS) ? e : window.event;//volgorde = volgorde +100
 //alert('keyPress' + volgorde);
 if(myevent.ctrlKey||myevent.altKey)
 {
  //alert('keyPress');
  if(isNS){return false;}else{event.cancelBubble=true; return false; };
 }
 else
 {
  return true;
 } 
}*/

function keyUPhandler(e)
{
 var myevent = (isNS) ? e : window.event;
 if(myevent.keyCode == 17) // ctrl_key
 {
  ctrlKeyDown = false;
 }
 else if(myevent.keyCode == 18) // alt_key
 {
  altKeyDown = false;
 } 
 else
 {
  return true;
 }
}


document.oncontextmenu = mischandler;
document.onmousedown = mousehandler;
document.onmouseup = mousehandler;
document.onkeydown = keyDownhandler;
//document.onkeypress = keyPresshandler;
document.onkeyup = keyUPhandler;

//Einde Script verbergen
//-->