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.oncontextmenu = nocontextmenu;   

document.onmousedown = norightclick;