Question

I am trying to create a serial number checker.

Serial Numbers are in ranges
A87594 – A92778
AB34534 – AC23405
B23933 – C344444

I was able to get the numbers to work using range() for the first serial number example, I’m guessing I need to use explode() but I wasn’t sure how to explode the letters into a variable and the numbers into a seperate variable.

if($_POST['submit']) {

    $snum = $_POST['serial_number'];

    // 1952
    $jan01_jan07 = range(87594, 92478);

    if (in_array($snum, $jan01_jan07)) {
        echo 'You have a 1952 Widget';
    }
    else {
        echo 'Your serial number is unknown';
    }
}

Answer 1

You can try using strcmp, as it checks two strings, so you can check whether the incoming data is equal to or more than the lower bound and less than or equal to the upper bound, like this:

$data = $_POST['data']; // change this accordingly

if(strcmp($data, $lowerBound) >= 0 && strcmp($data, $upperBound) <= 0) {
    // successful match
}

As strcmp returns -1, 0, 1 if $data is before, the same as and after $lowerBound (dictionary ordered), so this works for strings as well.