对一个日期型对象怎么加一年,或加一个月
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> Date Add one </TITLE>
</HEAD>
<BODY onload="init()">
当前:<input type="text" id="s">
<BR>
<INPUT TYPE="button" onclick="addyear()" value="加一年">
<INPUT TYPE="button" onclick="addmonth()" value="加一月">
<SCRIPT LANGUAGE="JavaScript">
<!--
var date;
function init(){
date=new Date();
s.value=date.toLocaleString();
}
function addyear(){
date.setYear(date.getYear()+1);
s.value=date.toLocaleString();
}
function addmonth(){
date.setMonth(date.getMonth()+1);
s.value=date.toLocaleString();
}
//-->
</SCRIPT>
</BODY>
</HTML>