验证rails中是否存在多个属性之一

Question

在多语言应用程序中,用户可以输入他们的中文和英文名称.用户可以输入其中一个或两个,但必须至少输入一个名称.

class Person < ActiveRecord::Base
  validates :zh_name, :presence => true
  validates :en_name, :presence => true
  validates :fr_name, :presence => true
end

由于内置:validates_presence_of方法只能同时验证两个属性,有没有办法验证rails中至少有一个属性的存在？

像一个神奇的, validates_one_of :zh_name, :en_name, :fr_name

先感谢您,

Answer 1

validate :at_least_one_name

def at_least_one_name
  if [self.zh_name, self.en_name, self.fr_name].reject(&:blank?).size == 0
    errors[:base] << ("Please choose at least one name - any language will do.")
  end
end      

Answer 2

将@ micapam的答案更进一步,我可以建议:

validate :has_a_name

def has_a_name
  unless [zh_name?, en_name?, fr_name?].include?(true)
    errors.add :base, 'You need at least one name in some language!'
  end
end