php - 如何从给定的两个日期检查日值？

Question

I dont know if this question already asked before.

Actually i have two date:

$date1 = $DATABASE_VALUE;

$day1 = date('d', strtotime($date1)); // $date1 is my database value

$date2 = date('Y-m-d H:m:s');

$day2 = date('d', strtotime($date2)); // $date2 current date

and I need to Check this:

if($day1 <= $day2) {
   ...
}

It is working if $date1 has a date value (Like - 2014-06-12 10:20:50) and i have set a default value which is

0000-00-00 00:00:00

so when $date1 is not 0000-00-00 00:00:00 (could be 2014-06-12 10:20:50) then :

$date1 = "2014-06-12 10:20:50"; // database value

$day1 = date('d', strtotime($date1)); 

echo $day1; // returns 12 (which is correct)

But if $date1 is 0000-00-00 00:00:00 then

$day1 returns 01

WHY?

If its a behavior of strtotime() (Not Sure About That).

Then tell me What should i do if date comes 0000-00-00 00:00:00 ?

Please help..

Answer 1

You have to add extra condition to your if statement which checks if timestamp of $date1 is different from 0 (false). Somehow like this:

$date1 = $DATABASE_VALUE;
$day1 = date('d', $t1 = strtotime($date1)); // $date1 is my database value
$date2 = date('Y-m-d H:m:s');
$day2 = date('d', strtotime($date2)); // $date2 current date

if($t1 && $day1 <= $day2) {
    ...
}