What is required by strtotime to make a string/What are the defaults?

Question

In a recent question, someone asked if they could make a time just using the hour, minute, and AM/PM parts of a standard time format. This led to my question, what is needed to create a time using strtotime?

• Do you need to have a date? If one is not provided, what date does it choose?
• Do you need to have a time? What is the default?
• Do you need to have a year? Default?
• Month? Default?
• Day? Default?

I guess this is more of, what are the defaults for strtotime, but I'm curious to know.

Answer 1

1. No; today.
2. No; noon.
3. No; this year.
4. No; the current month.
5. No; the current day.

I don't know what happens if the current day is unavailable in a specified month (e.g. it's the 31st and you do strtotime('February'). Someone who has a server instance available where they can safely manipulate the system time could research that.

Answer 2

See http://www.gnu.org/software/tar/manual/html_node/Date-input-formats.html#SEC114 and http://us2.php.net/manual/en/function.strtotime.php

The default time when no time is supplied is "00:00:00" (midnight).

Answer 3

Do you need to have a date? -> No. You can use 'now' as a string which will set to current date/time.

Do you need to have a time? -> No. 00:00:00 +0100 is the default.

Do you need to have a year? -> No. It uses the date in the current year with 00:00:00 time.

Do you need to have a month? Yes. If you put just the year, it returns the current date/time.

Do you need to have a day? No. It uses the first day of the month/year provided (00:00:00 time).