How to add or subtract days, months, or years from a DateTime object in PHP?

In PHP, you can use the DateTime class to add or subtract days, months, or years from a DateTime object using the modify() method. Here's an example:

$date = new DateTime(); // Create a new DateTime object

// Add 5 days
$date->modify('+5 days');

// Subtract 1 month
$date->modify('-1 month');

// Add 2 years
$date->modify('+2 years');

// Output the modified date
echo $date->format('Y-m-d');

In the modify() method, you can specify the number of days, months, or years you want to add or subtract by using a date/time interval format.

Some examples:

+5 days adds 5 days.
-1 month subtracts 1 month.
+2 years adds 2 years.

You can modify the DateTime object multiple times by calling the modify() method multiple times.