Ruby on rails 3 嵌套形式不'；不显示作业

我最近跟随了一个关于嵌套表单的教程，并且做了与他在其他名称上做的基本相同的事情。我想在订单表单中嵌套分配，我想为该订单的每个面包创建一个分配，用户应该在表单中输入一个计数

我的控制器看起来像这样

 def new
   @order = Order.new
   @buns = Bun.all
   @buns.each do |bun|
     @order.assignments.build(:bun_id => bun.id)
   end
 end

  <%= form_for(@order) do |f| %>
    <div class="field">
      <%= f.label :user_id %><br />
      <%= f.number_field :user_id %>
    </div>
    <div id="assignments" class="field">
      <% f.fields_for :assignments do |builder| %>
        <div id="assignment" class="field">
          <%= builder.label :count, "Anzahl" %>
          <%= builder.text_field :count %>
          <%= builder.object.bun_id %>
        <% end %>
      </div>
    </div>
    <div class="field">
      <%= f.label :due_to %><br />
      <%= f.datetime_select :due_to %>
    </div>
    <div class="actions">
      <%= f.submit %>
    </div>
  <% end %>

而_形式部分看起来是这样的

 def new
   @order = Order.new
   @buns = Bun.all
   @buns.each do |bun|
     @order.assignments.build(:bun_id => bun.id)
   end
 end

  <%= form_for(@order) do |f| %>
    <div class="field">
      <%= f.label :user_id %><br />
      <%= f.number_field :user_id %>
    </div>
    <div id="assignments" class="field">
      <% f.fields_for :assignments do |builder| %>
        <div id="assignment" class="field">
          <%= builder.label :count, "Anzahl" %>
          <%= builder.text_field :count %>
          <%= builder.object.bun_id %>
        <% end %>
      </div>
    </div>
    <div class="field">
      <%= f.label :due_to %><br />
      <%= f.datetime_select :due_to %>
    </div>
    <div class="actions">
      <%= f.submit %>
    </div>
  <% end %>

分配模型是这样的：

attr_accessible :bun_id, :order_id, :count
belongs_to :bun
belongs_to :order

当我记录分配时，所有这些都应该生成，那么为什么字段没有呈现呢

---

谢谢你的帮助

您的erb中缺少等号（=）：

 <%= f.fields_for :assignments do |builder| %>

---

您的erb中缺少等号（=）：

 <%= f.fields_for :assignments do |builder| %>