如何在Rails的表单中发布分组的输入数据

# 用户模型
class User < ApplicationRecord
  has_many :addresses
  accepts_nested_attributes_for :addresses
end

# 地址模型
class Address < ApplicationRecord
  belongs_to :user
end

# 用户控制器
class UsersController < ApplicationController
  def new
    @user = User.new
    2.times { @user.addresses.build } # 创建两个空的地址对象
  end

  def create
    @user = User.new(user_params)
    if @user.save
      # 保存用户和地址对象
      redirect_to @user
    else
      render :new
    end
  end

  private

  def user_params
    params.require(:user).permit(:name, addresses_attributes: [:street, :city, :country])
  end
end

# 用户视图中的表单
<%= form_with(model: @user) do |form| %>
  <%= form.label :name %>
  <%= form.text_field :name %>

  <%= form.fields_for :addresses do |address_form| %>
    <%= address_form.label :street %>
    <%= address_form.text_field :street %>

    <%= address_form.label :city %>
    <%= address_form.text_field :city %>

    <%= address_form.label :country %>
    <%= address_form.text_field :country %>
  <% end %>

  <%= form.submit %>
<% end %>