Rails Rails 如何实现多态继承
class Member < ActiveRecord::Base
end
class Demander < Member
end
class Supplier < Member
end
如何在实现 Demander 特有的属性只在 Demander 中使用，Supplier 特有的属性只在 Supplier 中生效，公共的属性存在 Member 中
http://api.rubyonrails.org/classes/ActiveRecord/Inheritance.html
表结构：
- id: int
- type: string
class User < ActiveRecord::Base
end
class Group < User
end
group = Group.create
group.type
=> "Group"
user = User.create
user.type
=> "User"
多态的话，楼主是这个意思吗？
class Member < ActiveRecord::Base
# resource_id, int , 'demanders 或是 suppliers 的id'
# resource_type, string, 'Demander 或是 Supplier'
has_one :resource, :polymorphic => true
end
class Demander < Member
belongs_to :members, :as => :resource
end
class Supplier < Member
belongs_to :members, :as => :resource
end
我觉得单表继承也能实现你的需求
