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如何在未保存的记录之间创建关联

cocoon-gem ruby-on-rails-5 ruby-on-rails

0

RodneyT94 · 技术社区 · 8 年前

我创建了如下3个模型,并使用cocoon嵌套形式在它们之间创建关联。

class Unit < ApplicationRecord
  has_many :mapping_categories, -> { distinct }, dependent: :destroy, inverse_of: :unit

  accepts_nested_attributes_for :mapping_categories,
                                allow_destroy: true,
                                reject_if: :all_blank
end

class MappingCategory < ApplicationRecord
  belongs_to :unit
  has_many :mapping_items, -> { distinct }, dependent: :destroy, inverse_of: :mapping_category

  accepts_nested_attributes_for :mapping_items,
                                allow_destroy: true    
end

class MappingItem < ApplicationRecord
  belongs_to :mapping_category
  has_many :mapping_item_links
  has_many :linked_mapping_items, through: :mapping_item_links, dependent: :destroy
end

创建或更新单元时,单元表单中有许多mapping\u categories选项卡,每个mapping\u categories部分中有许多mapping\u items部分。

例如,我有映射类别A和映射类别B。我想将映射项1添加到映射类别A,将映射项2添加到映射类别B。问题是:由于这两个项尚未保存,如何在映射项1和映射项2之间创建关联?

2 回复 | 直到 8 年前

1

3

Oleh Sobchuk 8 年前

你能做到的

user = User.new(name: 'Jons', email: 'jons@qq.ww')
bank_account = BankAccount.new(number: 'JJ123456', user: user)
bank_account.save

这样将保存RAW和 user 和 bank_account

unit = Unit.new(mapping_categories: [mapping_category])
mapping_category = MappingCategory.new(mapping_items: [mapping_item])
mapping_item = MappingItem.new
unit.save

如果你想使用 nested_attributes

params = { mapping_categories: [mapping_items: [{.....}]}] }
Unit.create(params)

2

0

Asdrubal sameera207 8 年前

> contact = Contact.new(full_name: "Steve", email:"example@asdf.com")
 => #<Contact id: nil, full_name: "Steve", email: "example@asdf.com", created_at: nil, updated_at: nil>

> invoice = Invoice.new(contact_id: contact.id, invoice_type: "Something")
 => #<Invoice id: nil, contact_id: nil, invoice_type: "Something" created_at: nil, updated_at: nil>

> invoice.save
 => false