Remove characters before and after a value outputted from a swiped card!

I am making a clocking in machine for my company, we have decided to use swipe cards instead of using barcodes (why I dont know!!!) the only problem is that mag cards have two characters, one before and one after the value that is required i.e +000000000003? the value I really need is 000000000003
Is there a way of removing these two characters using php?

Thanks in advance

Try using substr

will prob look something like this

$string = '+000000000003?';
$newstring = substr(1,strlen($string) - 2);