带有 mongoid 的 rails 3 中的嵌套属性问题（未保存嵌套对象）答案

【问题标题】：Nested attributes problem in rails 3 with mongoid (nested objects aren`t saved)带有 mongoid 的 rails 3 中的嵌套属性问题（未保存嵌套对象）
【发布时间】：2011-05-24 09:31:40
【问题描述】：

所以我有一个简单的应用程序，如RailsCast about nested forms.，问题是当我提交表单（包括调查和问题）问题没有保存。

我的模型（调查，有很多问题）：

class Survey
  include Mongoid::Document
  field :name
  has_many :questions, :dependent => :destroy
  accepts_nested_attributes_for :questions, :allow_destroy => true
end

class Question
  include Mongoid::Document
  field :content
  belongs_to :survey
end

和调查总监：

def new
    @survey = Survey.new
    3.times {@survey.questions.build}
....

还有一个观点：

<%= form_for(@survey) do |f| %>
    <%= f.fields_for :questions do |builder| %>
    <%= builder.label :content, "Question" %><br />
    <%= builder.text_area :content, :rows => 3 %><br />
    <%= builder.check_box :_destroy %>
    <%= builder.label :_destroy, "Remove Question" %>
    <% end %>
...

在我的日志中我有：

    Started POST "/surveys" for 127.0.0.1 at 2011-05-24 13:26:51 +0400
  Processing by SurveysController#create as HTML
  Parameters: {"utf8"=>"G£ô", "authenticity_token"=>"tX0FfMiLbh1BwjuY4CuvAKt2UpTraY3vmdo58ocBnos=", "survey"=>{"name"=>"
Rails", "questions_attributes"=>{"0"=>{"content"=>"Are you fond of Rails?", "_destroy"=>"0"}, "1"=>{"content"=>"Rails is
 the best, ha?", "_destroy"=>"0"}, "2"=>{"content"=>"How many railscasts have you watched?", "_destroy"=>"0"}}}, "commit
"=>"Create Survey"}
MONGODB nested_attributes_development['surveys'].insert([{"name"=>"Rails", "_id"=>BSON::ObjectId('4ddb79dba5372914380000
69')}])
Redirected to http://localhost:3000/surveys/4ddb79dba537291438000069

【问题讨论】：

标签： ruby-on-rails-3 mongoid nested-attributes

【解决方案1】：

答案是在谷歌群组中找到的，所以我只是复制它：

MONGODB 
nested_attributes_development['surveys'].insert([{"name"=>"Rails", 
"_id"=>BSON::ObjectId('4ddb79dba5372914380000 
69')}])

这不会保存到未完成的问题集合默认为 mongoid。只需添加 has_many :questions, :dependent => :destroy , :autosave => 真的 这应该有效。

参见。 http://mongoid.org/docs/upgrading.html 了解更多详情。

【讨论】：