Q29 How can I calculate someone's age in years, months and days?

<script language="JavaScript"><!--
function getAge(dateString,dateType) {
/*
   function getAge
   parameters: dateString dateType
   returns: boolean

   dateString is a date passed as a string in the following
   formats:

   type 1 : 19970529
   type 2 : 970529
   type 3 : 29/05/1997
   type 4 : 29/05/97

   dateType is a numeric integer from 1 to 4, representing
   the type of dateString passed, as defined above.

   Returns string containing the age in years, months and days
   in the format yyy years mm months dd days.
   Returns empty string if dateType is not one of the expected
   values.
*/

    var now = new Date();
    var today = new Date(now.getYear(),now.getMonth(),now.getDate());

    var yearNow = now.getYear();
    var monthNow = now.getMonth();
    var dateNow = now.getDate();

    if (dateType == 1)
        var dob = new Date(dateString.substring(0,4),
                            dateString.substring(4,6)-1,
                            dateString.substring(6,8));
    else if (dateType == 2)
        var dob = new Date(dateString.substring(0,2),
                            dateString.substring(2,4)-1,
                            dateString.substring(4,6));
    else if (dateType == 3)
        var dob = new Date(dateString.substring(6,10),
                            dateString.substring(3,5)-1,
                            dateString.substring(0,2));
    else if (dateType == 4)
        var dob = new Date(dateString.substring(6,8),
                            dateString.substring(3,5)-1,
                            dateString.substring(0,2));
    else
        return '';

    var yearDob = dob.getYear();
    var monthDob = dob.getMonth();
    var dateDob = dob.getDate();

    yearAge = yearNow - yearDob;

    if (monthNow >= monthDob)
        var monthAge = monthNow - monthDob;
    else {
        yearAge--;
        var monthAge = 12 + monthNow -monthDob;
    }

    if (dateNow >= dateDob)
        var dateAge = dateNow - dateDob;
    else {
        monthAge--;
        var dateAge = 31 + dateNow - dateDob;

        if (monthAge < 0) {
            monthAge = 11;
            yearAge--;
        }
    }

    return yearAge + ' years ' + monthAge + ' months ' + dateAge + ' days';
}

document.write(getAge("19650104",1)+'<BR>');

document.write(getAge("650104",2)+'<BR>');

document.write(getAge("04/01/1965",3)+'<BR>');

document.write(getAge("04/01/65",4)+'<BR>');
//--></script>

<script language="JavaScript" type="text/javascript"><!--
function Age(monthDob,dayDob,yearDob) {
  var now = new Date();
  var yearNow = now.getYear();
  var monthNow = now.getMonth() + 1;
  var dayNow = now.getDate();

  var today = new Date(yearNow,monthNow,dayNow);

  if (yearNow < 100) {
    yearNow=yearNow+1900;
  }

  yearAge = yearNow - yearDob;
	
  if (monthNow <= monthDob) {
    if (monthNow < monthDob) {
      yearAge--;		
    } else {
      if (dayNow < dayDob) {
        yearAge--;
      }
    }
  }
  return yearAge
}
//--></script>