如何将嵌套表单中的select_tag转为等价的Rails表单助手？

我一直无法将嵌套属性局部视图schedtimerange_form中的select_tag转换为Rails表单助手select，该局部视图用于scheduleevent表单的嵌套属性schedtimeranges中，求等价写法。

原主表单代码 #

<%= form_with(model: scheduleevent, class: "contents", data: { controller: 'nested-form', nested_form_wrapper_selector_value: '.nested-form-wrapper' }) do |form| %>

... schedtimerange_form start ...

<%= select_tag "days[]",options_for_select(Date::DAYNAMES.zip((1..7))), id:"days[]", multiple: true, class: 'multis' %> 

<% end %>

局部视图调用代码 #

<template data-nested-form-target="template">
  <%= form.fields_for :schedtimeranges, Schedtimerange.new, child_index: 'NEW_RECORD' do |schedtimerange| %>
     <%= render "schedtimerange_form", form: schedtimerange %>
  <% end %>
</template>
<%= form.fields_for :schedtimeranges do |schedtimerange| %>
     <%= render "schedtimerange_form", form: schedtimerange %>
<% end %>

原schedtimerange_form代码 #

<div data-new-record="<%= form.object.new_record? %>">
  <div class="w-full">
    <div data-controller="select">
     <%= select_tag "days[]",options_for_select(Date::DAYNAMES.zip((1..7))), id:"days[]", multiple: true, class: 'multis' %> </div>
  </div>
  <div>
    <div class="w-full mb-2">
      <label class="form_label"><%= t("scheduling_events_new_lbl_starttime") %> </label>
      <div class="pr-4"><%= form.text_field :start_time, data: { controller: "flatpickr", flatpickr_enable_time: true, flatpickr_no_calendar: true,
             flatpickr_date_format: "h:i K" }, class: 'form_control', placeholder: "#{t("scheduling_events_new_lbl_starttime")}" %> </div>
    </div>
    <div class="w-full mb-4">
      <label class="form_label"><%= t("scheduling_events_new_lbl_endtime") %> </label>
      <div class="pr-4"><%= form.text_field :end_time, data: { controller: "flatpickr", flatpickr_enable_time: true, flatpickr_no_calendar: true, flatpickr_date_format: "h:i K" }, class: 'form_control', placeholder: "#{t("scheduling_events_new_lbl_endtime")}" %> </div>
    </div>
    <div class="w-full">
      <button type="button" class="font-medium text-red-600 dark:text-red-500 hover:underline" data-action="nested-form#remove">Remove Times</button>
    </div>
  </div><%= form.hidden_field :_destroy %>
</div>

将schedtimerange_form中的select_tag替换为Rails表单助手select，利用嵌套表单的form对象自动生成正确的参数命名，适配嵌套属性结构：

<%= form.select :days, Date::DAYNAMES.zip(1..7), {}, multiple: true, class: 'multis' %>

关键说明： #

• 第一个参数:days对应Schedtimerange模型的属性（需确保模型中days是数组类型，比如用数据库text类型配合serialize :days, Array，或PostgreSQL的array类型）
• 第二个参数保留原有的选项生成逻辑Date::DAYNAMES.zip(1..7)
• 第三个参数{}是选项配置（如include_blank等，无需求则留空）
• 第四个参数传递HTML属性，包含multiple: true和样式类class: 'multis'
• Rails会自动生成符合嵌套结构的name属性（如scheduleevent[schedtimeranges_attributes][0][days][]）和正确的id，无需硬编码days[]，确保表单提交时参数能正确绑定到嵌套的schedtimeranges对象。

内容的提问来源于stack exchange，提问作者spacerobot