Regex for BIC check

Question

I wrote a regex for php function pregmatch which is like this:

^([a-zA-Z]){4}([a-zA-Z]){2}([0-9a-zA-Z]){2}([0-9a-zA-Z]{3})?$^

Now I need to check the consistency of an BIC string.

Something is wrong with it... it is always correct. And I have no idea why.

The code I use is something like this:

/**
 * Checks the correct format from the 
 * @param string $bic
 * @return boolean
 */
public function checkBic($bic)
{
    $bic = $this->cleanFromSeparators($bic);
    if (preg_match($this->getBicCompare(), $bic)) {
        return true;
    } else {
        return false;
    }
}

private function getBicCompare()
{
    return "^([a-zA-Z]){4}([a-zA-Z]){2}([0-9a-zA-Z]){2}([0-9a-zA-Z]{3})?$^";
}

EDIT:

Here are some references for BIC format from the swift account:

http://www.sage.co.uk/sage1000v2_1/form_help/workingw/subfiles/iban_and_bic.htm

http://en.wikipedia.org/wiki/ISO_9362

http://www.swift.com/products_services/bic_and_iban_format_registration_bic_details?rdct=t

an example BIC would be:

NOLADE21STS

OPSKATWW

The regex should only return true if the string consists of the following code: its length is eight or eleven characters and that consists of:

Bank code - 4 alphabetic characters Country code - 2 letters Location code - 2 alphanumeric characters, except zero Branch code - 3 alphanumeric characters

These are the specifications.

So the length can be either 11 or 8, first 4 can be anything, then 2 letters is a must, then 2 numbers and optional 3 alphanumeric.

The following are not valid:

abcdefxx

abcdefxxyyy

These also are not valid:

aaaa11xx

aaaa11xxyyy

and so on.

Answer 1

You are using ^ as delimiter? You probably want something more like:

'/^[a-z]{6}[0-9a-z]{2}([0-9a-z]{3})?\z/i'