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

You can also use this format:

validates :foo, length: {minimum: 5, maximum: 5}, allow_blank: true

Or since your min and max are the same, the following will also work:

validates :foo, length: {is: 5}, allow_blank: true