rails accepted_nested_attributes和：reject_if

Question

我有一個嵌套屬性的窗體。現在在我的:reject_if =>聲明中，我想檢查嵌套模型上的屬性，例如first_record?有沒有辦法訪問這種方法？在我看來，你只能訪問提交的屬性散列，例如檢查一個字段是否爲空。謝謝！

Answer 1

根據文檔http://api.rubyonrails.org/classes/ActiveRecord/NestedAttributes/ClassMethods.html

另外，：reject_if還接受了使用方法的象徵：

class Member < ActiveRecord::Base 
    has_many :posts 
    accepts_nested_attributes_for :posts, :reject_if => :new_record? 
end 

class Member < ActiveRecord::Base 
    has_many :posts 
    accepts_nested_attributes_for :posts, :reject_if => :reject_posts 

    def reject_posts(attributed) 
    attributed['title'].blank? 
    end 
end 

這應該爲你工作。基本上這意味着在自定義功能中，你可以做任何你想做的事情。