Styjun

You cannot compare date-strings. It is good habit to use PHP's DateTime object instead:

$paymentDate = new DateTime(); // Today
echo $paymentDate->format('d/m/Y'); // echos today! 
$contractDateBegin = new DateTime('2001-01-01');
$contractDateEnd = new DateTime('2015-01-01');

if (
 $paymentDate->getTimestamp() > $contractDateBegin->getTimestamp() && 
 $paymentDate->getTimestamp() < $contractDateEnd->getTimestamp())
 echo "is between";
else
 echo "NO GO!"; 

If hours matter:

$paymentDate = strtotime(date("Y-m-d H:i:s"));
$contractDateBegin = strtotime("2014-01-22 12:42:00");
$contractDateEnd = strtotime("2014-01-22 12:50:00");

if($paymentDate > $contractDateBegin && $paymentDate < $contractDateEnd) 
 echo "is between";
 else 
 echo "NO GO!"; 
 

You are comparing the dates as strings, which won't work because the comparison is lexicographical. It's the same issue as when sorting a text file, where a line 20 would appear after a line 100 because the contents are not treated as numbers but as sequences of ASCII codes. In addition, the dates created are all wrong because you are using a string format string where a timestamp is expected (second argument).

Instead of this you should be comparing timestamps of DateTime objects, for instance:

 $paymentDate = date_create();
 $contractDateBegin = date_create_from_format('d/m/Y', '01/01/2001');
 $contractDateEnd = date_create_from_format('d/m/Y', '01/01/2015');

Your existing conditions will then work correctly.

Based on luttken's answer. Thought I'd add my twist :)

function dateIsInBetween(DateTime $from, DateTime $to, DateTime $subject)

 return $subject->getTimestamp() > $from->getTimestamp() && $subject->getTimestamp() < $to->getTimestamp() ? true : false;


$paymentDate = new DateTime('now');
$contractDateBegin = new DateTime('01/01/2001');
$contractDateEnd = new DateTime('01/01/2016');

echo dateIsInBetween($contractDateBegin, $contractDateEnd, $paymentDate) ? "is between" : "NO GO!";

Another solution would have been to consider date written as Ymd.

Written in this "format" this is much easy to compare dates.

$paymentDate = date('Ymd'); // on 4th may 2016, would have been 20160504
$contractBegin = 20010101;
$contractEnd = 20160101;
echo ($paymentDate >= $contractBegin && $paymentDate <= $contractEnd) ? "Between" : "Not Between";

It will always work for every day of the year and do not depends on any function or conversion (PHP will consider the int value of $paymentDate to compare with the int value of contractBegin and contractEnd).

Use directly

$paymentDate = strtotime(date("d-m-Y"));
$contractDateBegin = strtotime("01-01-2001");
$contractDateEnd = strtotime("01-01-2015");

Then comparison will be ok cause your 01-01-2015 is valid for PHP's 32bit date-range, stated in strtotime's manual.

If you need bracket dates to be dynamic ..

$todayStr = date('Y-m-d');
$todayObj=date('Y-m-d', strtotime($todayStr));
$currentYrStr = date('Y');
$DateBegin = date('Y-m-d', strtotime("06/01/$currentYrStr"));
$DateEnd = date('Y-m-d', strtotime("10/01/$currentYrStr"));
if (($todayObj > $contractDateBegin) && ($paymentDate < $contractDateEnd))
 $period="summer";
else
 $period="winter"; 

An other solution (with the assumption you know your date formats are always YYYY/MM/DD with lead zeros) is the max() and min() function. I figure this is okay given all the other answers assume the yyyy-mm-dd format too and it's the common naming convention for folders in file systems if ever you wanted to make sure they sorted in date order.

As others have said, given the order of the numbers you can compare the strings, no need for strtotime() function.

Examples:

$biggest = max("2018/10/01","2018/10/02");

The advantage being you can stick more dates in there instead of just comparing two.

$biggest = max("2018/04/10","2019/12/02","2016/03/20");

To work out if a date is in between two dates you could compare
the result of min() and max()

$startDate="2018/04/10";
$endDate="2018/07/24";
$check="2018/05/03";
if(max($startDate,$check)==min($endDate,$check))
 // It's in the middle

It wouldn't work with any other date format, but for that one it does. No need to convert to seconds and no need for date functions.

The above methods are useful but they are not full-proof because it will give error if time is between 12:00 AM/PM and 01:00 AM/PM . It will return the "No Go" in-spite of being in between the timing .
Here is the code for the same:

$time = '2019-03-27 12:00 PM';

$date_one = $time; 
$date_one = strtotime($date_one);
$date_one = strtotime("+60 minutes", $date_one);
$date_one = date('Y-m-d h:i A', $date_one);

$date_ten = strtotime($time); 
$date_ten = strtotime("-12 minutes", $date_ten); 
$date_ten = date('Y-m-d h:i A', $date_ten);

$paymentDate='2019-03-27 12:45 AM';

$contractDateBegin = date('Y-m-d h:i A', strtotime($date_ten)); 
$contractDateEnd = date('Y-m-d h:i A', strtotime($date_one));

echo $paymentDate; 
echo "---------------"; 
echo $contractDateBegin; 
echo "---------------"; 
echo $contractDateEnd; 
echo "---------------";

$contractDateEnd='2019-03-27 01:45 AM';

if($paymentDate > $contractDateBegin && $paymentDate < $contractDateEnd) 
 
 echo "is between";
 
else
 
 echo "NO GO!"; 

Here you will get output "NO Go" because 12:45 > 01:45.

To get proper output date in between, make sure that for "AM" values from 01:00 AM to 12:00 AM will get converted to the 24-hour format. This little trick helped me.

Simple solution:

function betweenDates($cmpDate,$startDate,$endDate) 
 return (date($cmpDate) > date($startDate)) && (date($cmpDate) < date($endDate));