Nested fields inside table

Render nested fields inside a table, say have code

<table>
  <%= f.fields_for :tasks do |task_form| %>
    <tr class="fields">
      <td>
        <%= task_form.text_field :name %>
      </td>
      <td><%= task_form.link_to_remove 'Remove' %></td>
    </tr>
  <% end %>
  <tr>
    <td><%= f.link_to_add 'Add', :tasks %></td>
  </tr>
</table>

After render, outside each tr there will a additional hidden field with value of task id, Rails add f.hidden_field(:id) after the rendered field_for block. In order to make this hidden field inside each tr, we can pass option include_id: false to fields_for, and add hidden id field manually, so now our code becomes

<table>
  <%= f.fields_for :tasks, :include_id => false do |task_form| %>
    <tr class="fields">
      <td>
        <%= task_form.hidden_field :id %>
        <%= task_form.text_field :name %>
      </td>
      <td><%= task_form.link_to_remove 'Remove' %></td>
    </tr>
  <% end %>
  <tr>
    <td><%= f.link_to_add 'Add', :tasks %></td>
  </tr>
</table>

it’s much better.

ref http://apidock.com/rails/ActionView/Helpers/FormBuilder/fields_for_nested_model

Nested fields inside table with fields_for