Magnetic Strip Reader, Event detector + read card

Question

I'm trying to make a program in Windows 10 that is able to detect when a magnetic card passes through the Magnetic Strip Reader and reads the info that is in the card and puts it in a log.txt with the date and time.

So far I made this:

<?php
    while(true){
        if(/*event*/){
            $cardRead = /*cardInfo*/;
            $date = date(Y/m/d);
            $time = time(H:i:s);
            $txt = "$date, $time, $cardRead\n";
            $myfile = fopen("log.txt", "w");
            fwrite($myfile, $txt);
        }
    }
?>

1. Is there any code in php or javascript to get the event and the cardInfo?
2. Is it possible to keep the code running while the computer is turned on? What should I put on the while condition to achieve it?

Thank you so much for your help.