public function getPrefix()
    {
        if ($this->prefix == null) {
            $this->prefix = substr($this->msisdn, 0, 3);
        }

        return $this->prefix;
    }
public function getPrefix()
    {
        if ($this->prefix == null) {
            $this->prefix = substr($this->msisdn, 0, 3);
        }

        return $this->prefix;
    }
public function getPrefix ( ) { if ( $ this -> prefix == null ) { $ this -> prefix = substr ( $ this -> msisdn , 0 , 3 ) ; } return $ this -> prefix ; }
Returns the prefix of the MSISDN number.

@return string The prefix of the MSISDN number
Returns the prefix of the MSISDN number .