javascript keycode使用示例：

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

<script type="text/javascript">
   function keyEvent()
   {
    if(event.keyCode==13)
     alert("Enter Pressed!");
    if(event.keyCode==37)
     alert("Left Pressed!");
    if(event.keyCode==38)
     alert("Up Pressed!");
    if(event.keyCode==39)
     alert("Right Pressed!");
    if(event.keyCode==40)
     alert("Down Pressed!");
    if(event.keyCode==116)
     alert("F5 Pressed!");
   };
   document.onkeydown = keyEvent;
  </script>
</head>
<body>
event适用于IE
</body>
</html>