Rails -将嵌套参数从表单传递到控制器

# app/models/user.rb
class User < ApplicationRecord
  has_one :address
  accepts_nested_attributes_for :address
end

# app/models/address.rb
class Address < ApplicationRecord
  belongs_to :user
end

<!-- app/views/users/_form.html.erb -->
<%= form_with model: @user, local: true do |form| %>
  <%= form.label :name %>
  <%= form.text_field :name %>

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

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

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

# app/controllers/users_controller.rb
class UsersController < ApplicationController
  def new
    @user = User.new
    @user.build_address
  end

  def create
    @user = User.new(user_params)
    if @user.save
      redirect_to @user, notice: 'User was successfully created.'
    else
      render :new
    end
  end

  private

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

# 确保在视图中正确使用 fields_for
<%= form.fields_for :address do |address_form| %>
  ...
<% end %>

# 确保控制器的 strong parameters 正确
def user_params
  params.require(:user).permit(:name, address_attributes: [:id, :street, :city])
end