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    <h5>你好呀，现在时间是 &nbsp;&nbsp;<span class="timespan"></span></h5>
    <script>
        function writeCurrentDate() {
            var now = new Date();
            var year = now.getFullYear(); //得到年份
            var month = now.getMonth();//得到月份
            var date = now.getDate();//得到日期
            var day = now.getDay();//得到周几
            var hour = now.getHours();//得到小时
            var minu = now.getMinutes();//得到分钟
            var sec = now.getSeconds();//得到秒
    　　     var MS = now.getMilliseconds();//获取毫秒
            var week;
            month = month + 1;
            if (month < 10) month = "0" + month;
            if (date < 10) date = "0" + date;
            if (hour < 10) hour = "0" + hour;
            if (minu < 10) minu = "0" + minu;
            if (sec < 10) sec = "0" + sec;
            if (MS < 100) MS = "0" + MS;
            var arr_week = new Array("星期日", "星期一", "星期二", "星期三", "星期四", "星期五", "星期六");
            week = arr_week[day];
            var time = "";
            time = year + "年" + month + "月" + date + "日" + " " + hour + ":" + minu + ":" + sec + " " + week;
            document.getElementsByClassName('timespan')[0].innerHTML=time
            var timer = setTimeout("writeCurrentDate()", 1000);
        }
        writeCurrentDate()
    </script>
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