Sandeep's Nook: JavaScript Page

Age Calculator

Below is the Age Calculator script that can be used to find out one's age. Users have just to type in their full date of birth and the script will tell them their age. Type in the Month you were born, the Date and the Year in the format shown. Then to find your age just click the Get Age button. Clicking the button will result in your age being shown in Years, Months and Days.

Author: Sandeep Gangadharan
Home Page: http://www.sivamdesign.com/home/

The script is given below:

This goes in the HEAD of the html file:

<!--
function getAge() {
 month = document.form1.month.value;
 date = document.form1.date.value;
 year = document.form1.year.value;

if (month != parseInt(month)) { alert('Type Month of birth in digits only!'); return false; }
 if (date != parseInt(date)) { alert('Type Date of birth in digits only!'); return false; }
 if (year != parseInt(year)) { alert('Type Year of birth in digits only!'); return false; }
 if (year.length < 4) { alert('Type Year of birth in full!'); return false; }

today = new Date();
 dateStr = today.getDate();
 monthStr = today.getMonth();
 yearStr = today.getFullYear();

theYear = yearStr - year;
 theMonth = monthStr - month;
 theDate = dateStr - date;

var days = "";
 if (monthStr == 0 || monthStr == 2 || monthStr == 4 || monthStr == 6 || monthStr == 7 || monthStr == 9 || monthStr == 11) days = 31;
 if (monthStr == 3 || monthStr == 5 || monthStr == 8 || monthStr == 10) days = 30;
 if (monthStr == 1) days = 28;

document.form1.inYears.value = theYear;

if (month < monthStr && date > dateStr) { document.form1.inYears.value = parseInt(document.form1.inYears.value) + 1;
                                           document.form1.inMonths.value = theMonth; }
 if (month < monthStr && date <= dateStr) { document.form1.inMonths.value = theMonth; }
 else if (month == monthStr && (date < dateStr || date == dateStr)) { document.form1.inMonths.value = 0; }
 else if (month == monthStr && date > dateStr) { document.form1.inMonths.value = 11; }
 else if (month > monthStr && date <= dateStr) { document.form1.inYears.value = document.form1.inYears.value - 1;
                                                 document.form1.inMonths.value = ((12 - -(theMonth)) + 1); }
 else if (month > monthStr && date > dateStr) { document.form1.inMonths.value = ((12 - -(theMonth))); }

if (document.form1.inMonths.value == '12') {document.form1.inMonths.value=0; document.form1.inYears.value=parseInt(document.form1.inYears.value)+1}
 if (date < dateStr) { document.form1.inDays.value = theDate; }
 else if (date == dateStr) { document.form1.inDays.value = 0; }
 else { document.form1.inYears.value = document.form1.inYears.value - 1; document.form1.inDays.value = days - (-(theDate)); }
  }
// -->
</script>

This goes in the BODY of the html file: