取当前日期的前一天

[mgan]

如何让取当前日期的前一天

function init(){
var today = new Date();
year = today.getYear();
month = today.getMonth();
day = today.getDate();
day = day;
month = month+1;
var sday = new String(day);
var smonth = new String(month);
if(smonth.length == 1)
smonth = "0"+smonth;
if(sday.length == 1 )
sday = "0"+sday;
form1.start_date.value = year+"-"+smonth+"-"+sday;


}
这个是取当前日期

如何取当前日期的前一天呢?
我也在想啊

[ice_berg16]

var today = new Date();
today.setDate(today.getDate()-1);
alert(today.toLocaleString());

[clare2003]

<script>
var Yday=new Array(2);
Yday[0]=new Array(0,31,28,31,30,31,30,31,31,30,31,30,31);
Yday[1]=new Array(0,31,29,31,30,31,30,31,31,30,31,30,31);


function init(){
var today = new Date();
sYear = today.getYear();
smonth = today.getMonth()+1;
sday = today.getDate();
var yn=0;
if (sYear%400==0 || sYear%100!=0 && sYear%4==0 )
yn=1;
if((smonth==1)&&(sday==1))
{
sYear=sYear-1;
smonth=12;
sday=31;

}
else if(sday==1)
{
sday=(yn==1)?Yday[1][smonth-1]:Yday[0][smonth-1]
smonth=smonth-1

}
else
{
sday=sday-1;

}
alert(sYear+"-"+smonth+"-"+sday);


}
init()

</script>

[mgan]

3Q