捕捉浏览器的刷新与关闭 兼容ie、ff
<script language="javascript">var MSG_UNLOAD="确定离开?";var UnloadConfirm = {};//启用监听浏览器刷新、关闭的方法UnloadConfirm.set = function(confirm_msg){ window.onbeforeunload = function(event){ event = event || window.event; event.returnValue = confirm_msg; }}//关闭监听浏览器刷新、关闭的方法UnloadConfirm.clear = function(){ window.onbeforeunload = function(){};}UnloadConfirm.set(MSG_UNLOAD);</script>