JS倒计时打开指定网页

<script type="text/javascript">
    function countDown(secs, surl) {
        var jumpTo = document.getElementById('jumpTo');
        jumpTo.innerHTML = secs;
        if (--secs > 0) {
            setTimeout("countDown(" + secs + ",'" + surl + "')", 1000);
        }else {
            location.href = surl;
        }
    }     
</script>

<span id="jumpTo">5</span>秒后自动跳转到首页
<script type="text/javascript">countDown(5, 'http://www.baidu.com');</script>