Valid date or timestamp

Question

How do you do the following in PHP?

Check to see a time passed into a function is a valid date or a timestamp (valid meaning after 1970 time)?

If neither, throw an error.

I was thinking

if(ctype_digit($time)) {
     if($time > time_in_1970) {
         // good
     } else {
         // bad
     }
} else {
   $date_from_time = strtotime($time);

   if($date_from_time === false) {
     // error

Can you make an example of an invalid value? – Pekka Dec 03 '13 at 02:13 — Pekka, Dec 03 '13 at 02:13

score 2 · Answer 1 · edited May 23 '17 at 12:16

2

You can do like below:

function validateDate($date, $format = 'Y-m-d H:i:s')
{
    $d = DateTime::createFromFormat($format, $date);
    return $d && $d->format($format) == $date;
}

var_dump(validateDate('2012-02-28 12:12:12')); # true
var_dump(validateDate('2012-02-30 12:12:12')); # false
var_dump(validateDate('2012-02-28', 'Y-m-d')); # true
var_dump(validateDate('28/02/2012', 'd/m/Y')); # true
var_dump(validateDate('30/02/2012', 'd/m/Y')); # false
var_dump(validateDate('14:50', 'H:i')); # true
var_dump(validateDate('14:77', 'H:i')); # false
var_dump(validateDate(14, 'H')); # true
var_dump(validateDate('14', 'H')); # true

^{function was copied from this answer or php.net}

Or you can use checkdate() function of php like below:

function IsDate( $Str )
{
  $Stamp = strtotime( $Str );
  $Month = date( 'm', $Stamp );
  $Day   = date( 'd', $Stamp );
  $Year  = date( 'Y', $Stamp );

  return checkdate( $Month, $Day, $Year );
}

edited May 23 '17 at 12:16

Community

1
1

answered Dec 03 '13 at 02:18

Suresh Kamrushi

15,627
13
75
90

That's good code to generally validate a date, but why use it? It's a timestamp. If it's a number, it can by definition never have an invalid value. – Pekka Dec 03 '13 at 02:20
1

The first code block copied from http://php.net/manual/en/function.checkdate.php without attribution. Please don't do that, it's plagiarism and not allowed. Always provide a link to the original source. Thanks! – Pekka Dec 03 '13 at 02:22
1

Not for the first code block. [PHP preg_match with working regex](http://stackoverflow.com/q/12322824) – Pekka Dec 03 '13 at 02:25

score 2 · Answer 2 · answered Dec 03 '13 at 02:21

2

As long as the timestamp is greater than 0, it is a valid timestamp.

A timestamp of 0 = Dec 31, 1969

echo date("Y-m-d", 0);

This is because a UNIX timestamp is the measurement of seconds since the Epoch, AKA Dec 31, 1969

answered Dec 03 '13 at 02:21

dockeryZ

3,981
1
20
28

The Epoch is 1st of January, 1970 UTC. – Ja͢ck Dec 03 '13 at 02:24
Eh, I'm only off by one millisecond. I was going by what I received at this sandbox http://sandbox.onlinephpfunctions.com/code/dbd0161c4976782352e33c434f86043608f8ab32 – dockeryZ Dec 03 '13 at 02:31
1

Regardless, any timestamp greater than zero is valid. – dockeryZ Dec 03 '13 at 02:35
I agree with that. What I don't agree with is calling Dec 31, 1969 the Epoch =P – Ja͢ck Dec 03 '13 at 02:41

Valid date or timestamp

2 Answers2