Rails:用于在创建新子记录时选择现有父级的表单？

class Parent < ApplicationRecord
  has_many :children
  accepts_nested_attributes_for :children
end

<%= form_for @parent do |f| %>
  <%= f.label :name %>
  <%= f.text_field :name %>

  <%= f.fields_for :children do |child_form| %>
    <%= child_form.label :name %>
    <%= child_form.text_field :name %>
  <% end %>

  <%= f.submit %>
<% end %>

class ParentsController < ApplicationController
  def new
    @parent = Parent.new
    @parent.children.build
  end

  def create
    @parent = Parent.new(parent_params)
    if @parent.save
      # 保存成功的处理逻辑
    else
      # 保存失败的处理逻辑
    end
  end

  private

  def parent_params
    params.require(:parent).permit(:name, children_attributes: [:name])
  end
end