$.ajaxSetup( {
    //设置ajax请求结束后的执行动作
    complete :
        function(XMLHttpRequest, textStatus) {
            // 通过XMLHttpRequest取得响应头，sessionstatus
            var sessionstatus = XMLHttpRequest.getResponseHeader("REDIRECT");
            if (sessionstatus == "REDIRECT") {
            	localStorage.setItem("MESSAGE","账户异地登录，被踢下线！");
                var win = window;
                while (win != win.top){
                    win = win.top;
                }
                
                win.location.href= XMLHttpRequest.getResponseHeader("CONTEXTPATH");
            }
        }
});