ruby on rails -使用回形针嵌套表单

Question

我有一个名为posts的模型，它有许多附件。

附件模型正在使用回形针。

我做了一个独立的模型来创建附件，它工作得很好，这是这里指示的视图(https://github.com/thoughtbot/paperclip):

<% form_for :attachment, @attachment, :url => @attachment, :html => { :multipart => true } do |form| %>
  <%= form.file_field :pclip %>
  <%= form.submit %>
<% end %>

post中的嵌套表单是这样的:

<% @attachment = @posts.attachments.build %>
<%= form_for(@posts) do |f| %>
  <% if @posts.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@posts.errors.count, "error") %> prohibited this post from being saved:</h2>
      <ul>
      <% @posts.errors.full_messages.each do |msg| %>
        <li><%= msg %></li>
      <% end %>
      </ul>
    </div>
  <% end %>
  <div class="field">
    <%= f.label :name %><br />
    <%= f.text_field :name %>
  </div>
  <div class="field">
    <%= f.label :description %><br />
    <%= f.text_area :description %>
  </div>
  <div class="field">
    <%= f.fields_for :attachments, @attachment, :url => @attachment, :html => { :multipart => true } do |at_form| %>
      <%= at_form.file_field :pclip %>
    <% end %>
  </div>
  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

创建了一个附件记录，但它是空的。文件未上传。与此同时，该职位已成功创建…

任何想法?

Answer 1

表单定义中缺少:multipart选项:

<% @attachment = @post.attachments.build %>
<%= form_for @post, :html => { :multipart => true } do |f| %>
  <% if @post.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@post.errors.count, "error") %> prohibited this post from being saved:</h2>
      <ul>
      <% @post.errors.full_messages.each do |msg| %>
        <li><%= msg %></li>
      <% end %>
      </ul>
    </div>
  <% end %>
  <div class="field">
    <%= f.label :name %><br />
    <%= f.text_field :name %>
  </div>
  <div class="field">
    <%= f.label :description %><br />
    <%= f.text_area :description %>
  </div>
  <div class="field">
    <%= f.fields_for :attachments, @attachment do |at_form| %>
      <%= at_form.file_field :pclip %>
    <% end %>
  </div>
  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

另外，你的@posts变量应该是@post(单个ActiveRecord实例，而不是一个ActiveRecord实例数组)。