C++ Date and Time

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The C++ standard library doesn't provide any proper date type. C++ inherits the structs and functions for date and time manipulation from the C language. To access date and time related functions and structures, you have to use/include a header file in your C++ program named time.h.

There are four time-related types: clock_t, time_t, size_t, and tm. The types clock_t, size_t and time_t are capable of representing the system time and date as some sort of integer.

The structure type tm holds the date and time in the form of a C structure having the elements given here in these statements:

struct tm
{
	int tm_sec;   	// seconds of minutes from 0 to 61
	int tm_min;   	// minutes of hour from 0 to 59
	int tm_hour;  	// hours of day from 0 to 24
	int tm_mday;  	// day of month from 1 to 31
	int tm_mon;   	// month of year from 0 to 11
	int tm_year;  	// year since 1900
	int tm_wday;  	// days since Sunday
	int tm_yday;  	// days since January 1st
	int tm_isdst; 	// hours of daylight savings time
}

The tm structure is very important when working with the date and time in either C or C++ language. This structure holds the date and time in the form of a C structure. Most of the time related functions makes use of tm structure. Let's take some examples on date and time in C++ for complete understanding on C++ date and time.

C++ Date and Time Example

This C++ program simply prints the local and UTC date and time on the screen.

/* C+ Date and Time - Example Program of C++ Date and Time
 * This program prints local date and time, UTC date and
 * time on the output screen */

#include<iostream.h>
#include<conio.h>
#include<time.h>

void main()
{
	clrscr();

	time_t now = time(0);   // current system date/time

	char* dt = ctime(&now);   // convert in string form

	cout<<"Local date and time is:-\n\t\t"<<dt<<"\n";

	tm *gmtm = gmtime(&now);   // converting now to tm struct for UTC date/time
	dt = asctime(gmtm);
	cout<<"UTC date and time is:-\n\t\t"<<dt;

	getch();
}

Here is the sample output of the above C++ program:

C++ Date Example

This C++ program prints the current or today's date on the output screen.

/* C++ Date and Time - Example Program of C++ Date and Time
 * This program prints today's date on the output screen */

#include<iostream.h>
#include<conio.h>
#include<time.h>

void main()
{
	clrscr();

	time_t now = time(0);
	tm *ltm = localtime(&now);
	cout<<"Today is ";
	cout<<ltm->tm_mday<<"/"<<1+ltm->tm_mon<<"/";
	cout<<1900+ltm->tm_year<<"\n";

	getch();
}

Here is the sample output of this C++ program:

C++ Time Example

This C++ program prints the current time on the output screen.

/* C++ Date and Time - Example of C++ Date and Time
 * This program prints current date on the output
 * output screen in C++ */

#include<iostream.h>
#include<conio.h>
#include<time.h>

void main()
{
	clrscr();

	time_t now = time(0);
	tm *ltm = localtime(&now);
	cout<<"The current time is ";
	cout<<1+ltm->tm_hour<<":";
	cout<<1+ltm->tm_min<<":";
	cout<<1+ltm->tm_sec<<"\n";

	getch();
}

Below is the sample run of the above C++ program:

C++ Date and Time Complete Program

This is the complete version of the date and time programs (as shown above) in C++.

/* C++ Date and Time - Example of C++ Date and Time
 * This program demonstrates the working of date
 * and time in C++ program */

#include<iostream.h>
#include<conio.h>
#include<stdlib.h>
#include<time.h>

void main()
{
	clrscr();
	char choice, ans;

	time_t now = time(0);
	tm *ltm = localtime(&now);

	do
	{
		cout<<"1. Time\n";
		cout<<"2. Date\n";
		cout<<"3. Month\n";
		cout<<"4. Year\n";
		cout<<"5. All\n";
		cout<<"6. Exit\n";
		cout<<"\nEnter your choice (1-6) ";
		cin>>choice;
		clrscr();
		switch(choice)
		{
			case '1':
				 cout<<"The current time is ";
				 cout<<1+ltm->tm_hour<<":";
				 cout<<1+ltm->tm_min<<":";
				 cout<<1+ltm->tm_sec<<"\n";
				 break;
			case '2':
				cout<<"Today's date is ";
				cout<<ltm->tm_mday<<"\n";
				break;
			case '3':
				cout<<"It's ";
				cout<<1+ltm->tm_mon<<"th month\n";
				break;
			case '4':
				cout<<"This is ";
				cout<<1900+ltm->tm_year<<"\n";
				break;
			case '5':
				cout<<"Time: "<<1+ltm->tm_hour<<":";
				cout<<1+ltm->tm_min<<":";
				cout<<1+ltm->tm_sec<<"\n";
				cout<<"Date: "<<ltm->tm_mday<<"\n";
				cout<<"Month: "<<1+ltm->tm_mon<<"\n";
				cout<<"Year: "<<1900+ltm->tm_year<<"\n";
				break;
			case '6':
				exit(1);
			default:
				cout<<"Wrong choice..!!..Press a key to exit..\n";
				getch();
				exit(2);
		}
		cout<<"\nWant to check more ? (y/n).. ";
		cin>>ans;
		cout<<"\n";
	}while(ans=='y' || ans=='Y');

	getch();
}

Here are some sample runs of the above C++ program: