Script to Disable Default F5 key using java script

function disableKey(event) {

 if (!event)
  event = window.event;
 if (!event)
  return;

 var keyCode = event.keyCode ? event.keyCode : event.charCode;
 if (keyCode == 116 || (event.ctrlKey && keyCode == 82)) {
   /* window.status = "F5 key detected! Attempting to disabling default
   * response."; window.setTimeout("window.status='';", 2000);
   */
  if (event.preventDefault)
   event.preventDefault();

  //IE (exclude Opera with !event.preventDefault):
  if (document.all && window.event && !event.preventDefault) {
   event.cancelBubble = true;
   event.returnValue = false;
   event.keyCode = 0;
  }

  return false;
 }
a
}

function setEventListener(eventListener) {
 if (document.addEventListener)
  document.addEventListener('keypress', eventListener, true);
 else if (document.attachEvent)
  document.attachEvent('onkeydown', eventListener);
 else
  document.onkeydown = eventListener;
}

function unsetEventListener(eventListener) {
 if (document.removeEventListener)
  document.removeEventListener('keypress', eventListener, true);
 else if (document.detachEvent)
  document.detachEvent('onkeydown', eventListener);
 else
  document.onkeydown = null;
}

setEventListener(disableKey)