How to handle date and time with PHP?

Question

I need to do a little bit more complicated calculations with time and date values from my MySQL database with PHP.

I need to add or substract different values from a given date.

For example:

• Substracting 1 Month
• Substracting 30 Days
• Substracting 4 Weeks
• Adding 4 Month
• Adding 3 Month
• Adding 90 Days
• Adding 2 Years

Please note that there is a difference between substracting 1 Month, 4 Weeks or 30 Days.

What's the preferred way of doing this? Is there any clever library or can I do this with PHP's own functions?

Answer 1

From http://php.net/manual/en/function.strtotime.php

<?php
echo strtotime("now"), "\n";
echo strtotime("10 September 2000"), "\n";
echo strtotime("+1 day"), "\n";
echo strtotime("+1 week"), "\n";
echo strtotime("+1 week 2 days 4 hours 2 seconds"), "\n";
echo strtotime("next Thursday"), "\n";
echo strtotime("last Monday"), "\n";
?>

You can add a second parameter to make it add to given time:

echo strtotime("+1 week",$timestamp)