function promptOnClose(e){
                var promptString = '您确定要离开吗？';
                return promptString;
            }
            
            if (window != top) {
                top.location.href = "http://www.escience.gov.cn";
            }
            else {
                if (window.Event) {
                    window.onbeforeunload = function(event){
                        return promptOnClose(event);
                    }
                }
                else {
                    window.onbeforeunload = function(){
                        return promptOnClose(event);
                    }
                }
            }

?

?

? ?Javascript 监控浏览器的状态：当刷新或点击浏览器右上角的关闭按钮时，提示用户，