A simple little trick in PHP for when you need to make sure that a value doesn’t drop below zero. For example, you might be subtracting a discount from a basket total and not want the amount to be paid to become negative.
You could do this using a condition like this:-
$total = -8;
echo $total > 0 ? $total : 0; // Outputs '0'However, PHP has an method for doing this for us. We can use the max method.
$value = -9;
echo max($value, 0); // Outputs '0'All max does is return the larger number. So if $value is negative in this example 0 will be the larger number and be returned. If $value was positive, it would be greater than 0 and therefore $value would be returned.