brick / postcode Goto Github PK

function verifyPostcode(&$postcode)
    {
        // Permitted letters depend upon their position in the postcode.
        $alpha1 = '[abcdefghijklmnoprstuwyz]'; // Character 1
        $alpha2 = '[abcdefghklmnopqrstuvwxy]'; // Character 2
        $alpha3 = '[abcdefghjkstuw]'; // Character 3
        $alpha4 = '[abehmnprvwxy]'; 
        $alpha5 = '[abdefghjlnpqrstuwxyz]';
        
       
        // Expression for postcodes: AN NAA, ANN NAA, AAN NAA, and AANN NAA
        $pcexp[0] = '/^('.$alpha1.'{1}'.$alpha2.'{0,1}[0-9]{1,2})([0-9]{1}'.$alpha5.'{2})$/';
        // Expression for postcodes: ANA NAA
        $pcexp[1] = '/^('.$alpha1.'{1}[0-9]{1}'.$alpha3.'{1})([0-9]{1}'.$alpha5.'{2})$/';
        // Expression for postcodes: AANA NAA
        $pcexp[2] = '/^('.$alpha1.'{1}'.$alpha2.'[0-9]{1}'.$alpha4.')([0-9]{1}'.$alpha5.'{2})$/';
        // Exception for the special postcode GIR 0AA
        $pcexp[3] = '/^(gir)(0aa)$/';
    
        // Load up the string to check, converting into lowercase and removing spaces
        $postcode = strtolower($postcode);
        $postcode = str_replace (' ', '', $postcode);
    
        // Assume we are not going to find a valid postcode
        $valid = false;
    
        // Check the string against the six types of postcodes
        foreach ($pcexp as $regexp) {
            if (preg_match($regexp, $postcode, $matches)) {
                $postcode = strtoupper ($matches[1] . ' ' . $matches [2]);
                $valid = true;
                break;
            }
        }
    
        return $valid;
    }