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