js 获取当前时间 YYYY-MM-DD

if($('#ctl00_ContentPlaceHolder_VPN_EFFECTDATE_CalendarPicker_VPN_EFFECTDATE_ctl00_ContentPlaceHolder_VPN_EFFECTDATE_CalendarPicker_VPN_EFFECTDATE_T').val() != ""){
var effectdate=
$('#ctl00_ContentPlaceHolder_VPN_EFFECTDATE_CalendarPicker_VPN_EFFECTDATE_ctl00_ContentPlaceHolder_VPN_EFFECTDATE_CalendarPicker_VPN_EFFECTDATE_T').val();
              
var tody = new Date(); 
nian = tody.getFullYear();
month = tody.getMonth() + 1; 
day = tody.getDate(); 
       month =month <10?"0"+month :month 
                        day=day<10?"0"+day:day

var jt=nian+"-"+month+"-"+day;

if(effectdate <jt)
{
alert("希望生效时间不能小于今天!");
return false;
}

}