<script>
var serverNow=new Date('<%=now%>');
var clientS=0;
document.write("<span id='timespan'></span>");
setInterval("clientS++;timespan.innerHTML=new Date(serverNow.getTime() + clientS*1000).toLocaleString()+' 星期'+'日一二三四五六'.charAt(new Date().getDay());",1000);
</script>
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2010-5-31修改
<script>
var serverNow=new Date();
serverNow.getDate("<%=now%>");
var clientS=0;
document.write("<span id='timespan'></span>");
setInterval("clientS++;timespan.innerHTML=(new Date(serverNow.getTime() + clientS*1000)).toLocaleString()+' 星期'+'日一二三四五六'.charAt(new Date().getDay());",1000);
</script>
2012-07-06修改 几日兼容非ie内核浏览器 toLocaleString 在非ie内核不能返回本地时间字符串
<script>
var serverNow=new Date();
serverNow.getDate("<%=now%>");
var clientS=0;
document.write("<span id='timespan'></span>");
setInterval("clientS++; var cTime=new Date(serverNow.getTime() + clientS*1000); timespan.innerHTML=cTime.getFullYear() + '年' + (cTime.getMonth()+1) + '月' + cTime.getDate() + '日 ' + cTime.getHours() + ':' + cTime.getMinutes() + ':' + cTime.getSeconds() + ' 星期'+'日一二三四五六'.charAt(new Date().getDay());",1000);
</script>
参考 js显示当地时间
http://www.hlc8.com/a.asp?id=148