在嵌套表单中使用分隔符格式化值

Question

我正在使用Ryan Bates nested_form gem (https://github.com/ryanb/nested_form)并遇到一个问题，当涉及到在我的'edit'表单上格式化值时。

我目前在我的一些"未嵌套"表单字段上使用这个，它工作得很好!但是，当我以相同的方式对其中一个嵌套元素进行格式化时，我得到一个'未定义方法错误''

' unnested Fields'的代码

value: number_with_delimiter(f.object.reserve_price, precision: 2)

编辑时嵌套的表单字段

<div id="products">
          <%= f.fields_for :products, :wrapper => false do |product_form| %>
            <div class="form-group">
                <div class="input-group col-md-4">
                    <div class="input-group-addon">$</div>
                <%= product_form.text_field :retail_weekly_price, class: "form-control", placeholder: 'Retail Weekly Rate Card', required: true, (***add value call results in error***) %>
               <div class="input-group-addon">.00</div>
            </div>
            </div>
          </div>
          <% end %>
        </div>

新增错误日志

ActionView::Template::Error (undefined method `retail_weekly_price' for #<Location:0x007fd46baa35b0>):
   160:                 <div class="form-group">
   161:                     <div class="input-group col-md-4">
   162:                         <div class="input-group-addon">$</div>
   163:                     <%= product_form.text_field :retail_weekly_price, class: "form-control", placeholder: 'Retail Weekly Rate Card', required: true, value: number_with_currency(f.object.retail_weekly_price, precision: 2) %>
   164:                    <div class="input-group-addon">.00</div>
   165:                 </div>
   166:                 </div>
   app/views/locations/_edit_form.html.erb:163:in `block (2 levels) in    _app_views_locations__edit_form_html_erb__1967616523010840695_70275187628360'
   app/views/locations/_edit_form.html.erb:137:in `block in   _app_views_locations__edit_form_html_erb__1967616523010840695_70275187628360'
   app/views/locations/_edit_form.html.erb:1:in `_app_views_locations__edit_form_html_erb__1967616523010840695_70275187628360'
   app/views/locations/edit.html.erb:1:in `_app_views_locations_edit_html_erb__1956197158500275006_70275237765300'

Answer 1

使用

value: number_to_currency(product_form.object.retail_weekly_price, precision: 2)

不是

value: number_with_currency(f.object.retail_weekly_price, precision: 2)

由于retail_weekly_price字段在products表中。

f.object将返回您在nested_form_for中引用的Location实例，并且由于retail_weekly_price字段不存在于locations表中，您收到错误

undefined method 'retail_weekly_price' for #<Location

product_form.object将返回fields_for引用的Product的实例。通过它访问retail_weekly_price字段不会有任何问题。

另外，ActionView 辅助方法名称是number_to_currency而不是number_with_currency