js计算时间差简单代码

<script language=javascript>
getday();
function getday()
{
  var oldyear = 2007;
  var oldmonth = 7;
  var olddate = 5;

  var now = new date();
  var nowyear = now.getfullyear();
  var nowmonth = now.getmonth() + 1;
  var nowdate = now.getdate();
 
  var syear = nowyear - oldyear;
  var smonth = nowmonth - oldmonth;
  var sdate = nowdate - olddate;

  var passdate = syear * 365 + smonth * 30 + sdate ;
  document.write("已工作了<font color='red'>"+ passdate + "</font>天");
}
</script>