您可以像这样定义每个属性的自定义验证类：

class Person < ApplicationRecord
  validates :email, presence: true, email: true
end

class EmailValidator < ActiveModel::EachValidator
  def validate_each(record, attribute, value)
    unless value =~ /\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\z/i
      record.errors.add attribute, (options[:message] || "is not an email")
    end
  end
end

您可以使用自定义验证器（https：//guides.rubyonrails.org/active_record_validations.html#performing-custom-validations）或使用validate方法：

class Model < ActiveRecord
  validate :hard_validator_for_name

  private

  def hard_validator_for_name
     if self.name != 'VALID NAME'
       errors.add(:name, "name not valid")
     end
  end
end