Validate IBAN number with PHP

// functioan
function IbanValidation($value) {
    $iban = false;
    $value= strtoupper(trim($value));
 
// Country US (can be changed into your country)
if(preg_match('/^US\d{7}0[A-Z0-9]{16}$/', $value)) {
        $number = substr($value,4,22).'2927'.substr($value,2,2);
        $number = str_replace(
 
// Arrays in arrays
array('A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'),
 
array(10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35),
            $number
        );
 
        $iban = (1 == bcmod($number,97)) ? true:false;
    }
// return
return $iban;
}