Rails 3 - Custom Validation

Question

I\'m somewhat confused by my options for custom validations in Rails 3, and i\'m hoping that someone can point me in the direction of a resource that can help with my current is

Answer 1

you can use custom validation method, as described here:

class Vehicle < ActiveRecord::Base
  validate :model_year_valid_for_trim

  def model_year_valid_for_trim
    if #some validation code for model year and trim
      errors.add(:model_years, "some error")
    end
  end

end