我想限制用户可以创建的模型对象的数量.我已经尝试过以下但是没有用.我理解rails 3.1中发生了一些变化,现在还不确定如何实现.
class User < ActiveRecord::Base has_many :things,:limit => 5,:dependent => :destroy # This doesn't work end class Things <ActiveRecord::Base belongs_to :user end
解决方法
尝试这样的事情：
class User < ActiveRecord::Base
has_many :things
end
class Things <ActiveRecord::Base
belongs_to :user
validate :thing_count_within_limit,:on => :create
def thing_count_within_limit
if self.user.things(:reload).count >= 5
errors.add(:base,"Exceeded thing limit")
end
end
end
编辑：更新为Rails 3