strtotime() fails to parse "00:20 AM" in datetime string

Question

I want to format a date for SQL, but I am getting an unexpected result:

echo date('Y-m-d H:i:s', strtotime("February 13 2022 10:08 PM")); //2022-02-13 22:08:00
echo date('Y-m-d H:i:s', strtotime("March 23 2022 00:20 AM")); //1970-01-01 00:00:00

How can I correctly parse these dates?

because time it not valid, it should be ``12:20 AM`` if it's 12 hours time instead of ``00:20 AM`` which represents 24-hours time style. — OMi Shah, Apr 14 '23 at 09:27
I would try using unix time. That way you will always know the format of the time. — Winston, Apr 14 '23 at 09:39
I have no choice, I'm migrating data from a JSON to a MySQL database. I have to fix the invalid time somehow then. Thanks, @OMiShah! — Dumitru, Apr 14 '23 at 09:43
Does this answer your question? [Php string date a date into another format?](https://stackoverflow.com/questions/38263332/php-string-date-a-date-into-another-format) — axcl, Apr 14 '23 at 09:51
Are all the timestamps in same format shown, with 24-hour time? Maybe you can just strip off those meridiem indicators (AM/PM) before converting. — showdev, Apr 15 '23 at 07:53
Does this answer your question? [PHP strtotime(): date showing '1970-01-01 ' after conversion](https://stackoverflow.com/questions/50174713/php-strtotime-date-showing-1970-01-01-after-conversion) — showdev, Apr 15 '23 at 08:34

mickmackusa · Answer 1 · 2023-04-15T08:08:44.190

If the goal is to repair the data because you are tasked with using flawed data, you can use a regular expression to cut off any foul or unneeded AM or PM substrings.

Code: (Demo)

$tests = [
    "February 13 2022 10:08 PM",
    "March 23 2022 00:20 AM",
    "April 3 2022 11:20 PM",
    "May 28 2022 12:20 AM",
    "June 12 2022 21:20 PM",
    "July 4 2022 13:20 AM",
];

$tests = preg_replace(
    [
        '/(?:0\d|1[01]):\d{2}\K AM/', // 00:00 through 11:59 do not need AM
        '/(?:2\d|1[3-9]):\d{2}\K [AP]M/',  // 13:00 through 23:59 do not need AM or PM
    ],
    '',
    $tests
);
var_export($tests);
foreach ($tests as $test) {
    echo "\n" . date('Y-m-d H:i:s', strtotime($test));
}

Output:

array (
  0 => 'February 13 2022 10:08 PM',
  1 => 'March 23 2022 00:20',
  2 => 'April 3 2022 11:20 PM',
  3 => 'May 28 2022 12:20 AM',
  4 => 'June 12 2022 21:20',
  5 => 'July 4 2022 13:20',
)
2022-02-13 22:08:00
2022-03-23 00:20:00
2022-04-03 23:20:00
2022-05-28 00:20:00
2022-06-12 21:20:00
2022-07-04 13:20:00

score 1 · Answer 2 · edited Apr 14 '23 at 10:06

1

This is because strtotime("March 23 2022 00:20 AM") returns FALSE, because it is an invalid date as OMi Shah pointed out. And apparently FALSE being evaluated as 0 by date() function, try print date('Y-m-d H:i:s', FALSE); and see for yourself, it would print 1970-01-01 03:00:00 same as date('Y-m-d H:i:s', 0);

edited Apr 14 '23 at 10:06

Marcin Orlowski

72,056
11
123
141

answered Apr 14 '23 at 09:51

Michael G

31
4

score 1 · Answer 3 · answered Apr 15 '23 at 07:26

If you have invalid dates, you need to do error checking:

$unixTime = strtotime('March 23 2022 00:20 AM');
if ($unixTime === false) {
    // Report error
} else {
    $normalizedString = date('Y-m-d H:i:s', $unixTime);
}

Date parsing functions can often been too lenient (for example, strtotime('PDT') produces current time in PDT time zone), so it also doesn't hurt to convert back to the original format and see whether you get the same value back.

You may also want to fix errors, but that highly depends on what the errors look like and what resolution you want:

'March 23 2022 00:20 AM' // Replace 00:... AM dates with valid representation
'February 31 2023 09:55 PM' // Make it March 3? Throw error?
'(no data)' // Nothing fixable here

strtotime() fails to parse "00:20 AM" in datetime string

3 Answers3