日期比较

[ahancai]

我想限制日期输入框的日期必须小于今日，可是在javascript却没办法搞定，有谁能帮忙？我不想用vbscript。
var d,dd
var d=document.frm.Date1.value;
dd=d.split("-");

today = new Date()
thedat = new Date(dd[0],(dd[1]-1),dd[2])

msPerDay = 24 * 60 * 60 * 1000; // 计算一天的毫秒数
daysLeft = (thedat.getTime() - today.getTime()) / msPerDay;
daysLeft = Math.round(daysLeft);

if(daysLeft<0){
alert("不能选今日之前的日子");
document.frm.Date1.focus();
return false;
}

可惜我选了同一日的凌晨00:00:01，daysLeft还是会小于零

[hemeng]

<script language=javascript>
var d1 = "2003/5/8";
execScript('dim n : n = DateAdd("d", 25, "'+ d1 +'")','vbscript');
var d = new Date(n);
alert(d.getFullYear() + "年" + (d.getMonth() + 1) + "月" + d.getDate() + "日")
</script>