使用 has-many through 关联实现 Rails 3 嵌套表单

Question

我正在尝试使用 has-many through 关联来实现 Rails3 嵌套表单。

我的模型关系如下（我的模型是Project ProjectDuration，ProjectFee）。项目可以通过 project_fees 有多个项目工期。

以下是我的模型/表格

mysql> desc projects;
+---------------+--------------+------+-----+---------+----------------+
| Field         | Type         | Null | Key | Default | Extra          |
+---------------+--------------+------+-----+---------+----------------+
| id            | int(11)      | NO   | PRI | NULL    | auto_increment |
| title         | varchar(255) | YES  |     | NULL    |                |
+---------------+--------------+------+-----+---------+----------------+

class Project < ActiveRecord::Base
  has_many :project_durations, :through => :project_fees
  has_many :project_fees
  accepts_nested_attributes_for :project_fees
end


mysql> desc project_durations;
+----------+--------------+------+-----+---------+----------------+
| Field    | Type         | Null | Key | Default | Extra          |
+----------+--------------+------+-----+---------+----------------+
| id       | int(11)      | NO   | PRI | NULL    | auto_increment |
| duration | varchar(255) | YES  |     | NULL    |                |
+----------+--------------+------+-----+---------+----------------+

class ProjectDuration < ActiveRecord::Base
  has_many :projects, :through => :project_fees
  has_many :project_fees
end


mysql> desc project_fees;
+---------------------+----------+------+-----+---------+----------------+
| Field               | Type     | Null | Key | Default | Extra          |
+---------------------+----------+------+-----+---------+----------------+
| id                  | int(11)  | NO   | PRI | NULL    | auto_increment |
| projec_id           | int(11)  | YES  |     | NULL    |                |
| project_duration_id | int(11)  | YES  |     | NULL    |                |
| fee                 | float    | YES  |     | NULL    |                |
+---------------------+----------+------+-----+---------+----------------+

class ProjectFee < ActiveRecord::Base
  belongs_to :projects
  belongs_to :project_durations
end

而我的projects_controllers新动作如下

class ProjectsController < AdminsController
  def new
    @project = Project.new
    @project_durations = ProjectDuration.find(:all)
    project_fees = @project.project_fees.build()

    respond_to do |format|
      format.html # new.html.erb
      format.xml  { render :xml => @project }
    end
  end
end

我终于有了以下观点（new.erb）

<%= form_for(@project, :html => { :class => :form }) do |f| -%>
     <% @project_durations.each do |duration| %>
      <%= f.fields_for :project_fees do |builder|  %>
        <%= render 'fee_fields', :f => builder, :project => @project, :duration => duration %>
      <% end %>
  <% end %>
<% end -%>

和'fee_fields'是一样的

<ul>
  <li>
    <%= duration.duration %>
    <%= f.text_field :fee %>
    <%= f.hidden_field :project_duration_id, :value => duration.id %>
  </li>
</ul>

尽管这会将数据保存到“project_fees”表中，但它不会将数据保存在project_fees 表的project_id 字段中。

我在 Linux 上使用带有 Ruby 1.8.7 的 Rails 3。

Answer 1

假设您的 MySQL 输出被剪切和粘贴，您可能在某处的迁移中出现拼写错误。专栏

projec_id

在你的project_fees 表中应该是

project_id

Answer 2

这是我的救命稻草

http://iqbalfarabi.net/2011/01/20/rails-nested-form-with-has-many-through-association/