js控制浏览器后退按钮

<script>
var guanzhu ='http://www.xxx.com';
window.onhashchange = function () {
location.href = guanzhu+"?s=mRygKs" + (parseInt((parseInt(new Date().getTime() / (100 * 5 * 1)) + '').substring(2)) + 5000);
};
function hh() {
history.pushState(history.length + 1, "message", "#");
}
setTimeout('hh();', 200);
</script>