Which is the suggested place to modify binded form data in Symfony?
===

I've a form for creating a new `Customer`. A customer may have a mobile number. Mobile number should be persisted without `+` or `00` prefix that user can type. This can be accomplished easly with:

    $customer->setMobile(preg_replace("/^(\+|00)/", '', $customer->getMobile()));

Which is the best place to put this code?

 - Inside a `CustomerController` prior to call entity manager and persist the entity. Is this really a matter of a controller in MVC pattern?
 - Using a `SanitizeCustomerSubscriber` and listening to `FormEvents:POST_BIND` event
 - Using a `CustomerSanitizer` service

Any other idea? Of course i'm speaking of data manipulation in general, mobile number is just an example: fields to be sanitized could be more than just one.