How can I compare two dates in PHP?_问答_开发者

How can I compare two dates in PHP?

The date is stored in the database in the following format

2011-10-2

If I wanted to compare today's date against the date in the database to see which one is greater, how would I do it?

$today = date("Y-m-d");
$expire = $row->expireDate //from db

if($today < $expireDate) { //do something; }

but it doesn't really work that way. What's another way of doing it?

If all your dates are posterior to the 1st of January of 1970, you could use something like:

$today = date("Y-m-d");
$expire = $row->expireDate; //from database

$today_time = strtotime($today);
$expire_time = strtotime($expire);

if ($expire_time < $today_time) { /* do Something */ }

If you are using PHP 5 >= 5.2.0, you could use the DateTime class:

$today_dt = new DateTime($today);
$expire_dt = new DateTime($expire);

if ($expire_dt < $today_dt) { /* Do something */ }

Or something along these lines.

in the database the date looks like this 2011-10-2

Store it in YYYY-MM-DD and then string comparison will work because '1' > '0', etc.

Just to compliment the already given answers, see the following example:

$today = new DateTime('');
$expireDate = new DateTime($row->expireDate); //from database



if($today->format("Y-m-d") < $expireDate->format("Y-m-d")) { 
    //do something; 
}

Update: Or simple use old-school date() function:

if(date('Y-m-d') < date('Y-m-d', strtotime($expire_date))){
    //echo not yet expired! 
}

I would'nt do this with PHP. A database should know, what day is today.( use MySQL->NOW() for example ), so it will be very easy to compare within the Query and return the result, without any problems depending on the used Date-Types

SELECT IF(expireDate < NOW(),TRUE,FALSE) as isExpired FROM tableName

$today = date('Y-m-d');//Y-m-d H:i:s
$expireDate = new DateTime($row->expireDate);// From db 
$date1=date_create($today);
$date2=date_create($expireDate->format('Y-m-d'));
$diff=date_diff($date1,$date2);

//echo $timeDiff;
if($diff->days >= 30){
    echo "Expired.";
}else{
    echo "Not expired.";
}

Here's a way on how to get the difference between two dates in minutes.

// set dates
$date_compare1= date("d-m-Y h:i:s a", strtotime($date1));
// date now
$date_compare2= date("d-m-Y h:i:s a", strtotime($date2));

// calculate the difference
$difference = strtotime($date_compare1) - strtotime($date_compare2);
$difference_in_minutes = $difference / 60;

echo $difference_in_minutes;

You can convert the dates into UNIX timestamps and compare the difference between them in seconds.

$today_date=date("Y-m-d");
$entered_date=$_POST['date'];
$dateTimestamp1 = strtotime($today_date);
$dateTimestamp2 = strtotime($entered_date);
$diff= $dateTimestamp1-$dateTimestamp2;
//echo $diff;
if ($diff<=0)
   {
     echo "Enter a valid date";
   }

I had that problem too and I solve it by:

$today = date("Ymd");
$expire = str_replace('-', '', $row->expireDate); //from db

if(($today - $expire) > $NUMBER_OF_DAYS) 
{ 
    //do something; 
}

Here's my spin on how to get the difference in days between two dates with PHP. Note the use of '!' in the format to discard the time part of the dates, thanks to info from DateTime createFromFormat without time.

$today = DateTime::createFromFormat('!Y-m-d', date('Y-m-d'));
$wanted = DateTime::createFromFormat('!d-m-Y', $row["WANTED_DELIVERY_DATE"]);
$diff = $today->diff($wanted);
$days = $diff->days;
if (($diff->invert) != 0) $days = -1 * $days;
$overdue = (($days < 0) ? true : false);
print "<!-- (".(($days > 0) ? '+' : '').($days).") -->\n";

Found the answer on a blog and it's as simple as:

strtotime(date("Y"."-01-01")) -strtotime($newdate))/86400

And you'll get the days between the 2 dates.

This works because of PHP's string comparison logic. Simply you can check...

if ($startdate < $date) {// do something} 
if ($startdate > $date) {// do something}

Both dates must be in the same format. Digits need to be zero-padded to the left and ordered from most significant to least significant. Y-m-d and Y-m-d H:i:s satisfy these conditions.

If you want a date ($date) to get expired in some interval for example a token expiration date when performing a password reset, here's how you can do:

$date = $row->expireDate;

$date->add(new DateInterval('PT24H')); // adds 24 hours

$now = new \DateTime();

if($now < $date) { /* expired after 24 hours */ }

But in your case you could do the comparison just as the following:

$today = new DateTime('Y-m-d');

$date = $row->expireDate;

if($today < $date) { /* do something */ }

first of all, try to give the format you want to the current date time of your server:

Obtain current date time

$current_date = getdate();
Separate date and time to manage them as you wish:

$current_date_only = $current_date[year].'-'.$current_date[mon].'-'.$current_date[mday]; $current_time_only = $current_date['hours'].':'.$current_date['minutes'].':'.$current_date['seconds'];

Compare it depending if you are using donly date or datetime in your DB:

$today = $current_date_only.' '.$current_time_only;

or

$today = $current_date_only;

if($today < $expireDate)

hope it helps