[求助] 关于js对日期赋初值的问题

L@_@K<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title>Untitled Page</title>
</head>
<body>
    <form name="keyword" method="get" action="search.asp" target='_blank'>
        <tr>
            <td width="31%" height="40" align="right">
                發布時間：
            </td>
            <td width="69%" valign="center">
                <input name="fromdate" readonly="true" class="inputstyle" size="13" value="">
                <a href="javascript:cal1.popup();">
                    <img height="16" alt="點幾選擇日期" src="images/cal.gif" width="16" border="0">
                </a>&nbsp;至&nbsp;
                <input name="todate" readonly="true" class="inputstyle" size="13" value="" onclick="with(todate){value=value.replace('',getDateString())}">
                <a href="javascript:cal2.popup();">
                    <img height="16" alt="點幾選擇日期" src="images/cal.gif" width="16" border="0">
                </a>
                <script language="JavaScript">
<!--
function getToday()
{
    with(new Date())
    {
        return getFullYear()+"-"+(getMonth()<9?"0":"")+(getMonth()+1)+"-"+(getDate() <10?"0":"")+getDate();
    }
}
function getDayBefore6M()
{
    var today = new Date();
    var dayBefore6M = new Date(today.getFullYear(), (today.getMonth()-6), today.getDate());
    with(dayBefore6M)
    {
        return getFullYear()+"-"+(getMonth()<9?"0":"")+(getMonth()+1)+"-"+(getDate() <10?"0":"")+getDate();
    }
}
document.all.todate.value = getToday();
document.all.fromdate.value = getDayBefore6M();
//-->
                </script>
                <script language="JavaScript">
/*
var cal1 = new calendar1(document.forms['keyword'].elements['fromdate']);
cal1.year_scroll = true;
cal1.time_comp = false;
var cal2 = new calendar1(document.forms['keyword'].elements['todate']);
cal2.year_scroll = true;
cal2.time_comp = false;
*/
                </script>            </td>
        </tr>
    </form>
</body>
</html>