PHP date comparison and strtotime - php

Question

Using WIndows, XAMPP 5.6.8 I am building a simple web app in HTML and PHP.
I would like to compare a date retrieved from a database with today's date.
I have a function that successfully returns a string value (in the UK date format d-m-y).
My code so far is;
$expDate = get_api_data($id); // returns a string
var_dump($expDate); // this prints string(8) "31-12-19"
Using this $expDate value I would like to achieve something like;
if (strtotime('d-m-y', $expDate) > time()) { // if date > than today
echo 'date is greater than today';
}
elseif (strtotime('d-m-y', $expDate) < time()) { // if date < than today
echo 'date is less than today';
}
else {
echo 'date not found';
}
Currently I am receiving date is less than today - even though the date is 31-12-19. I'm not sure if I am approaching this the correct way?
Any help would be greatly appreciated as I have alreday spent a lot of time researching answers to no avail.

Answer 1

I got this error when executing your code
PHP Notice: A non well formed numeric value encountered
You should look at the doc in order to make a good usage of this function: http://php.net/manual/fr/function.strtotime.php
The first param should be a time, not a format.
By the way, i prefer use DateTime class to compare dates, you can do:
<?php
$expectedDate = \DateTime::createFromFormat('d-m-y', get_api_data($id));
$nowDate = new \DateTime();
if ($expectedDate > $nowDate) { // if date > than today
echo 'date is greater than today';
}
elseif ($expectedDate < $nowDate) { // if date < than today
echo 'date is less than today';
}
else {
echo 'date not found';
}

Answer 2

$formattedDate = DateTime::createFromFormat('d-m-y', $expDate);
$expDate= $formattedDate->getTimestamp();
if ($expDate > time()) { // if date > than today
echo 'date is greater than today';
.....
Try above code sample, try to use DateTime class if you have PHP 5.2.0 or higher http://php.net/manual/en/datetime.createfromformat.php . Then using that dateTime object you can do comparisons in a way you want e.g. in my sample I am doing it by time.
Your code will show a notice. if you turn on the php error reporting, you will observer it.