自测恒序时检测循环依赖

Question

我正在使用Rails 4.1.0在敏捷开发中构建应用程序。

我查找了有关这个问题的论坛:在自动加载常量顺序的同时检测到循环依赖，发现这是一个可能的错误，因为rails版本和因此更新了regarding来使用Rails 4.0.0

我得到了这一行的错误：<%= f.label :pay_type %>

<%= f.text_field :pay_type，ORDER::PAYMENT_TYPE，提示符：“选择付款方法”%> <%= f.submit“Place Order”%>

我的表格是：

<%= form_for(@order) do |f| %>
  <% if @order.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@order.errors.count, "error") %> prohibited this order from being saved:</h2>

      <ul>
      <% @order.errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
      </ul>
    </div>
  <% end %>

  <div class="field">
    <%= f.label :name %><br>
    <%= f.text_field :name, size: 40 %>
  </div>
  <div class="field">
    <%= f.label :address %><br>
    <%= f.text_area :address, rows: 3, cols: 40 %>
  </div>
  <div class="field">
    <%= f.label :email %><br>
    <%= f.text_field :email, size: 40 %>
  </div>
  <div class="field">
    <%= f.label :pay_type %><br>
    <%= f.text_field :pay_type, ORDER::PAYMENT_TYPE, prompt: 'Select a payment method' %>
  </div>
  <div class="actions">
    <%= f.submit 'Place Order' %>
  </div>
<% end %>

我的Order.rb是：

class Order < ActiveRecord::Base
    PAYMENT_TYPE = ["Check", "Credit Card", "Purchase Order"]
end

我仍然得到了错误，并在我的智囊团解决它，因为我必须提交这个星期一。( :'(这是完整的错误堆栈跟踪。有人能帮帮我吗！

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Answer 1

不是ORDER::PAYMENT_TYPE，是Order::PAYMENT_TYPE。注意Order类上的情况。使用ORDER将提高NameError。

您还希望更改用于:pay_type的输入助手，因为Order::PAYMENT_TYPE返回一个数组。

<%= f.select :pay_type, Order::PAYMENT_TYPE, include_blank: 'Select a payment method' %>

另外，对于“选择支付方法”文本，您希望使用include_blank选项而不是prompt来显示为默认选项。