PHP | date_modify() Function

The date_modify() function is an inbuilt function in PHP. Through the help of this function, we can modify or can alter the timestamp of DateTime object. The DateTime object and string modify are parameters in the calling function.

Syntax:

date_modify(DateTime $object, string $modify);

Parameters:
The function accepts two parameters as described below:

1. $object : This is a mandatory parameter. It specifies a DateTime object returned by date_create() .This object is modified by the above mentioned function.
2. $modify : This is also a mandatory parameter. This specifies a date/time string. It is incremented or decremented to modify the DateTime object.

Return Values :
This function returns a DateTime object on success. And returns FALSE on failure.

Below programs illustrate the date_modify() function :

Program 1 :

<?php
// PHP program to illustrate date_modify()
// function

// creating DateTime object
$date=date_create("2018-04-08");

// calling of date modify function
// with two required parameters
date_modify($date, "+15 days");

// printing the modified date in "y-m-d" format
echo date_format($date, "Y-m-d");
?>

Output:

2018-04-13

Program 2: This program will be increase months by one

<?php
// PHP program to illustrate date_modify()
// function

// creating a DateTime object
$date = date_create('2000-10-14');

// calling date_modify function with
// two required parameters
date_modify($date, '+1 month');

// printing the modified date
echo date_format($date, 'Y-m-d');
?>

Output:

2000-11-14

Reference
http://php.net/manual/en/datetime.modify.php