PartKeepr\AuthBundle\Validator\Constraints\UsernameValidator::validate PHP Method

    public function validate($value, Constraint $constraint)
    {
        if (!preg_match('/^[a-zA-Za0-9.\\-_\\/\\\\]{3,50}$/', $value, $matches)) {
            // If you're using the new 2.5 validation API (you probably are!)
            $this->context->buildViolation($constraint->message)->setParameter('%string%', $value)->addViolation();
        }
    }