js返回上一页和安全退出

<a href="javascript:if(confirm('您确定要返回吗？'))history.back();"><img src="img/fh.gif"/></a>

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<script language="javascript" type="text/javascript">function isExit() {var msg = "您确定要退出吗？";if (confirm(msg)==true){parent.location.href="<%=path%>/logout.jsp";}else{return false;}}</script><%session.setAttribute("loginUser", null);%>

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