Question

我试图保存我的模型，但未能保存它。

 #starship.rb

 class Starship < ApplicationRecord
    has_many :crew_members,inverse_of: :starship
    accepts_nested_attributes_for :crew_members

    has_many :holodeck_programs,inverse_of: :starship
    accepts_nested_attributes_for :holodeck_programs
 end

 #crew_member.rb

 class CrewMember < ApplicationRecord
   belongs_to  :starship
   accepts_nested_attributes_for :starship
   has_many :holodeck_programs,through: :starship
 end

 #holodeck_program.rb

 class HolodeckProgram < ApplicationRecord
   belongs_to :starship
   belongs_to :crew_member
 end

#controller

def create
  #Starship,CrewMember and HolodeckProgram are new via CrewMember.new
  @crew_member = CrewMember.new(crew_member_params)
  @crew_member.save
  .
  .
end
  .
  .
private
 def crew_member_params
  params.require(:crew_member).permit(:name,:division,:starship_id,
  starship_attributes: [:name,:id,
  holodeck_programs_attributes: [:title,:starship_id,:crew_member_id]])
 end

由于holodeck_programs_attributes中没有crew_member_id，因此会发生验证错误。

我不能使用inverse_of :: crew_member因为在crew_member.rb中通过

我该如何处理？

Answer 1

实际上，您可以在创建星舰时创建任意数量的crew_members，holodeck_programs。

但是你正在尝试为一个机组成员创建许多星舰，holodeck_programs，查看

def crew_member_params
  params.require(:crew_member).permit(:name,:division,:starship_id,
  starship_attributes: [:name,:id,
  holodeck_programs_attributes: [:title,:starship_id,:crew_member_id]])
 end

因此您需要将创建更改为

def create
  @starship = Starship.new(star_ship_params)
  @starship.save
end

和crew_member_params到

def star_ship_params
  params.require(:star_ship).permit(<attributes of star_ship>, holodeck_programs_attributes: [<attributes of holodeck_programs>], crew_members_attributes: [<attributes of crew_members>])
end

并确保您已相应地在视图中完成所有更改

请查看：{{3}}，了解有关嵌套属性及其用法的更多信息。

Rails has_many通过保存失败

1 个答案: