Here is an example of how the DateTime Structure works for C#. It's extremely basic and very easy to follow.
/*
This program finds out your Age using the DateTime structure in C#.
*/
using System;
class DOB{
private DateTime dtDob;
private DateTime dtNow;
private DateTime dtAge;
private int intDay;
private int intMonth;
private int intYear;
private int intHour;
private int intMinute;
private TimeSpan tsAge;
private int intAgeYear;
private int intAgeMonths;
private int intAgeDays;
private int intAgeHours;
private int intAgeMinutes;
public static void Main (String[] args) {
DOB objDob=new DOB();
objDob.getDob();
objDob.createDateObjects();
Console.WriteLine("Your Age in Years :" + objDob.getAgeInYears());
Console.WriteLine("Your Age in Months :" + objDob.getAgeInMonths());
Console.WriteLine("Your Age in Days :" + objDob.getAgeInDays());
Console.WriteLine("Your Age in Hours : " + objDob.getAgeInHours());
Console.WriteLine("Your Age in Minutes : " + objDob.getAgeInMinutes());
Console.WriteLine("Your Accurate Age is : " + objDob.getAgeInYears() + " Years " +
objDob.getMonthDiff() + " months " + objDob.getDayDiff() + " days");
}
/* get the date */
private void getDob() {
try {
Console.Write("Enter the Day u were born : " );
intDay=Console.ReadLine().ToInt32();
Console.Write("Month : ");
intMonth=Console.ReadLine().ToInt32();;
Console.Write("Year(yyyy) : ");
intYear=Console.ReadLine().ToInt32();
Console.Write("Hour(0-23) : ");
intHour=Console.ReadLine().ToInt32();
Console.Write("Minute(0-59) : ");
intMinute=Console.ReadLine().ToInt32();
}
catch (Exception e) {
Console.WriteLine(e.StackTrace);
Environment.Exit(0);
}
}
/* create the date objects */
private void createDateObjects() {
dtDob=new DateTime(intYear,intMonth,intDay,intHour,intMinute,0);
dtNow=DateTime.Now;
if (DateTime.Compare(dtNow,dtDob)==1)
tsAge=dtNow.Subtract(dtDob);
else {
Console.WriteLine("Future dates cannot be entered.");
Environment.Exit(0);
}
dtAge=new DateTime(tsAge.Ticks);
Console.WriteLine("Your date of birth :" + dtDob.Format("F",null));
}
/* calculates the age in Years */
private int getAgeInYears() {
intAgeYear=dtAge.Year-1;
return intAgeYear;
}
/* calculates the age in months */
private int getAgeInMonths() {
intAgeMonths=intAgeYear*12;
intAgeMonths=intAgeMonths+(dtAge.Month-1);
return intAgeMonths;
}
/* calculates the age in days */
private int getAgeInDays() {
if (dtDob.Year==dtNow.Year) {
intAgeDays=dtNow.DayOfYear-dtDob.DayOfYear;
}
else {
if(DateTime.IsLeapYear(dtDob.Year))
intAgeDays=366-dtDob.DayOfYear;
else
intAgeDays=365-dtDob.DayOfYear;
for (int i=dtDob.Year+1;i < dtNow.Year;i++) {
if (DateTime.IsLeapYear(i))
intAgeDays+=366;
else
intAgeDays+=365;
}
intAgeDays+=dtNow.DayOfYear;
}
return intAgeDays;
}
/* calculates the age in Hours */
private int getAgeInHours() {
intAgeHours=getAgeInDays() * 24;
intAgeHours=intAgeHours+(dtNow.Hour-dtDob.Hour);
return intAgeHours;
}
/* calculates the age in Minutes */
private int getAgeInMinutes() {
intAgeMinutes=getAgeInHours() * 60;
intAgeMinutes=intAgeMinutes+(dtNow.Minute-dtDob.Minute);
return intAgeMinutes;
}
/* calculates the month part of the accurate Age */
private int getMonthDiff() {
return getAgeInMonths()%12;
}
/* calculates the day part of the accurate Age */
private int getDayDiff() {
int intDayTemp1=getAgeInDays();
int intDayTemp2;
int intTempYear;
int intTempMonth;
int intTempDay=intDay;
if (dtNow.Year!=dtDob.Year) {
if (1==dtNow.Month) {
intTempYear=dtNow.Year-1;
intTempMonth=12;
}
else {
if(dtNow.Day < intTempDay)
intTempMonth=dtNow.Month-1;
else {
intTempMonth=dtNow.Month;
intTempDay=1;
}
intTempYear=dtNow.Year;
}
}
else {
if (1==dtNow.Month || dtDob.Month==dtNow.Month)
return getAgeInDays();
else {
if(dtNow.Day < intTempDay)
intTempMonth=dtNow.Month-1;
else {
intTempMonth=dtNow.Month;
intTempDay=1;
}
}
intTempYear=intYear;
}
dtNow=new DateTime(intTempYear,intTempMonth,intDay);
intDayTemp2=getAgeInDays();
return intDayTemp1-intDayTemp2;
}
}
/*
Result
------
D:\progs>dob
Enter the Day u were born : 1
Month : 1
Year(yyyy) : 2000
Hour(0-23) : 1
Minute(0-59) : 4
Your date of birth :Saturday, January 01, 2000 1:04:00 AM
Your Age in Years :1
Your Age in Months :17
Your Age in Days :520
Your Age in Hours : 12489
Your Age in Minutes : 749375
Your Accurate Age is : 1 Years 5 months 3 days
*/
