Ruby on Rails嵌套表格

Question

我有三種模型：Deal，Zipcode，DealIncludeZipcode。

現在，聯想看起來象下面這樣： -

新政型號：

class Deal < ActiveRecord::Base 
    has_many :deal_include_zipcodes, dependent: :destroy 
    has_and_belongs_to_many :zipcodes, dependent: :destroy 

    accepts_nested_attributes_for :deal_include_zipcodes,:reject_if => :reject_include_zipcodes, allow_destroy: true 

    private 
    def reject_include_zipcodes(attributes) 
     if attributes[:deal_id].blank? || attributes[:zipcode_id].blank? 
     if attributes[:id].present? 
      attributes.merge!({:_destroy => 1}) && false 
     else 
      true 
     end 
     end 
    end 
end 

class Zipcode < ActiveRecord::Base 
    has_and_belongs_to_many :deals 
end 


class DealIncludeZipcode < ActiveRecord::Base 
    belongs_to :deal 
    belongs_to :zipcode 
end 

鑑於我有一個複選框，取消勾選上它，我可以選擇多個郵政編碼從DealIncludeZipcode.But時選擇

現在我保存它沒有保存的數據。

我已經使用遷移加入郵編和交易模型，其中我的排除郵政編碼功能工作正常。

請提供一個soloution.I已經嘗試了各種方法，但沒有成功。

Answer 1

has_and_belongs_to_many整點是你沒有加入這兩個部分的模型。

class Deal < ActiveRecord::Base 
    has_and_belongs_to_many :zipcodes 
end 

class Zipcode < ActiveRecord::Base 
    has_and_belongs_to_many :deals 
end 

可以通過一個名爲deals_zipcodes 「無頭」 表連接。如果您想要加入模型，則需要使用has_many :through。

class Deal < ActiveRecord::Base 
    has_many :deal_zipcodes, dependent: :destroy 
    has_many :zipcodes, through: :deal_zipcodes 
end 

class DealZipcode < ActiveRecord::Base 
    belongs_to :deal 
    belongs_to :zipcode 
end 

class Zipcode < ActiveRecord::Base 
    has_many :deal_zipcodes, dependent: :destroy 
    has_many :deals, through: :deal_zipcodes 
end 

Answer 2

我認爲馬克斯的權利。所以，你的遷移應該是

create_table :deals do |t| 
    t.string :name 
    ... 
end 
create_table :zipcodes do |t| 
    t.string :zipcode 
    ... 
end 
create_table :deals_zipcodes do |t| 
    t.belongs_to :deal, index: true 
    t.belongs_to :zipcode, index: true 
end 

而且您的模型應該是

class Deal < ActiveRecord::Base 
    has_and_belongs_to_many :zipcodes 
end 
class Zipcode < ActiveRecord::Base 
    has_and_belongs_to_many :deals 
end 

你或許應該看一看的ActiveRecord guide，在那裏你會找到更多的解釋。