PHP DateTime equality

Question

How can I compare if two DateTime objects have the same day,month and year? The problem is they have different hours/min/seconds.

Answer 1

Casting into strings, or stripping away the hours/minutes/seconds is the only way

With strings:

if (gmdate("Ymd",$date1)==gmdate("Ymd",$date2)) {
  echo "Same day";
}

With time-ints:

$lowerbound=strtotime(gmdate("Y-m-d",$date1));
// s * m * h = 86400 sec/day
if ($date2>=$lowerbound && $date2<$lowerbound+86400) {
  echo "Same day";
}

[[Assuming $date1, $date2 are int dates in PHP- $intdate=strtotime($strdate) to convert]]

Answer 2

There's no nice way of doing that with DateTime objects. So you'll have to do, lets say, not so nice things.

$nDate1 = clone $date1;
$nDate2 = clone $date2;

//We convert both to UTC to avoid any potential problems.
$utc = new DateTimeZone('UTC');
$nDate1->setTimezone($utc);
$nDate2->setTimezone($utc);

//We get rid of the time, and just keep the date part.
$nDate1->setTime(0, 0, 0);
$nDate2->setTime(0, 0, 0);

if ($nDate1 == $nDate2) {
    //It's the same day
}

This will work, but like I said, it's not nice.

On a side note, recent experience tells me its always best to make sure both dates are on the same timezone, so I added the code for it just in case.

Answer 3

if(date('dmY', $date1) == date('dmY', $date2))

You can put it in a function...

function compare_dates($date1, $date2){
  if(date('dmY', $date1) == date('dmY', $date2))
    return true ;

  return false ;
}

is most useful ;)