The DateTimeImmutable::add() function is an inbuilt function in PHP which is used to add a number of days, months, years, hours, minutes and seconds to a created DateTimeImmutable object.
Syntax:
DateTimeImmutable DateTimeImmutable::add( DateInterval $interval )
Parameters: This function accepts a single parameter $interval which holds the number of days or months or years or hours or minutes or seconds which are going to be added to the given DateTimeImmutable object.
Return Values: This function returns the final DateTimeImmutable object after addition is done.
Below programs illustrate the DateTimeImmutable::add() function in PHP:
Program 1: This program uses DateTimeImmutable::add() function to add 2 days to the DateTimeImmutable object.
<?php // PHP program to illustrate DateTimeImmutable::add() // function     // Creating a new DateTimeImmutable::add() object $datetime = new DateTimeImmutable("2019-10-03T10:00:00");   // Initializing a date interval of 2 days $interval = 'P2D';   // Calling the add() function $datetime = $datetime->add(new DateInterval($interval));   // Getting a new date time in the // format of 'Y-m-d H:i:s' echo $datetime->format('Y-m-d H:i:s'); ?> |
2019-10-05 10:00:00
Program 2: This program uses DateTimeImmutable::add() function to add ‘P2Y5M2DT0H30M40S’ DateInterval to the DateTimeImmutable object.
<?php // PHP program to illustrate DateTimeImmutable::add() // function     // Creating a new DateTimeImmutable::add() object $datetime = new DateTimeImmutable("2019-10-03T10:00:00");   // Initializing a DateInterval object $interval = 'P2Y5M2DT0H30M40S';   // Calling the add() function $datetime = $datetime->add(new DateInterval($interval));   // Getting a new date time in the // format of 'Y-m-d H:i:s' echo $datetime->format('Y-m-d H:i:s'); ?> |
2022-03-05 10:30:40
Reference: https://www.php.net/manual/en/datetimeimmutable.add.php
