//页面置顶显示
if(window.self != window.top) {
        window.top.location = window.self.location;
}

//刷新上层页面
window.parent.main.document.location.reload();

//显示div

function   fnBlock(){
    document.getElementById("showMsg").style.display="block";
}

//隐藏div

function   fnNone(){
    document.getElementById("showMsg").style.display="none";
}

//4000毫秒后隐藏

function   timeControl(){

    window.setInterval("fnNone()",4000);

}