Question

所以我修改了我的索引视图，使其只根据名为fields的实例变量呈现特定字段，但是当我这样做时，除了生成错误的datetime字段之外它工作得很好。示例：undefined method empty?' for Tue, 22 Nov 2016 23:01:00 +0000:DateTime这是视图代码。

<p id="notice"><%= notice %></p>

<h1>Articles</h1>

<table>
  <thead>
    <% @fields = ["headline", "content","date", "locale", "classification" ]  unless @fields.present? %>
    <tr>
      <% @fields.each do |field| %>
        <th><%= "#{field.titleize}" %></th>
      <% end %>
    </tr>
  </thead>

  <tbody>
    <% @articles.each do |article| %>
      <tr>
        <% @fields.each do |field| %>
        <td><%= simple_format article.send(field) %></td>
        <% end %>
        <td><%= link_to 'Show', article %></td>
        <td><%= link_to 'Edit', edit_article_path(article) %></td>
        <td><%= link_to 'Destroy', article, method: :delete, data: { confirm: 'Are you sure?' } %></td>
      </tr>
    <% end %>
  </tbody>
</table>

<br>

<%= link_to 'New Article', new_article_path %>

这是模型代码

class Article
  include Mongoid::Document
  validates :classification,
    :inclusion  => { :in => [ 'unclassified', 'medical', 'non medical'] }
  validates :headline, presence: true
  validates :content, presence: true
  field :headline, type: String
  field :content, type: String
  field :classification, type: String
  field :weak_classification, type: String
  field :locale, type: String
  field :date, type: DateTime
end

我该如何解决这个问题？

Answer 1

您可以在之前将字段转换为string。

<%= simple_format article.send(field).to_s %>

或者更好地检查一个字段的类型并对其进行格式化。

def format_article_field(field)
  value = article.send(field)

  if value.kind_of?(DateTime)
    value.to_s(:short) # any format shortcut here
  else
    simple_format(value.to_s)
  end
end

<%= format_article_field field %>

Rails视图，未定义的方法`空？对于日期时间对象

1 个答案: