Rails: Validating min and max length of a string but allowing it to be blank

Question

I have a field that I would like to validate. I want the field to be able to be left blank, but if a user is entering data I want it to be in a certain format. Currently I am us

Answer 1

From the validates_length_of documentation:

validates_length_of :phone, :in => 7..32, :allow_blank => true

:allow_blank - Attribute may be blank; skip validation.