Question

我一直试图通过两个模型之间的关联来添加一个has_many; ＆＃39;空间＆＃39;和＆＃39;问题＆＃39;。在太空中，您可以添加将要添加的问题。我为关联创建了一个spaceQuestion模型。

目前，我能够看到要添加到空间的所有问题的列表，但是当我尝试添加空格时，我得到： undefined method`id＆＃39;对于nil：NilClass 并且它抱怨这一行： @space_question = SpaceQuestion.new（question_id：params [：question_id]，space_id：@ space.id）

这是我的代码：

spaces_controller.rb：

def questions
    @space_questions = @space.questions
    @other_questions = (Question.all - @space_questions)
  end

  def add_question
    @space_question = SpaceQuestion.new(question_id: params[:question_id], space_id: @space.id)

    respond_to do |format|
      if @space_question.save
        format.html { redirect_to questions_tenant_space_url(id: @space.id, tenant_id: @space.tenant_id)
          #notice: "User was successfully added to space"
          }
      else
        format.html { redirect_to questions_tenant_space_url(id: @space.id, tenant_id: @space.tenant_id),
          error: "Question was not added to space" }
      end
    end
  end

space.rb：

class Space < ActiveRecord::Base
  belongs_to :tenant
  belongs_to :department
  has_many :artifacts, dependent: :destroy

  has_many :user_spaces, dependent: :destroy
  has_many :users, through: :user_spaces

  has_many :space_questions, dependent: :destroy
  has_many :questions, through: :space_questions

question.rb：

class Question < ActiveRecord::Base
  belongs_to :user
  belongs_to :department

  has_many :space_questions
  has_many :spaces, through: :space_questions

  validates_presence_of :title, :details, :department
end

space_question.rb：

class SpaceQuestion < ActiveRecord::Base
  belongs_to :space
  belongs_to :question
end

questions.html.erb :(在空格视图中）

<% @other_questions.each do |other_question| %>
  <tr>
    <td><%= other_question.department.name %></td>
    <td><%= link_to other_question.title, question_path(other_question) %></td>
    <td><%= other_question.user.id %></td>
    <td>
      <%= link_to 'Add',
                  add_question_tenant_space_path(id: @space.id, tenant_id: @space.tenant_id, question_id: other_question.id),
                  :method => :put,
                  :class => 'btn btn-xs btn-success' %>
    </td>
  </tr>
<% end %>

Answer 1

除非您在该控制器中创建了一个前挂钩，否则您需要定义@space变量，而add_question方法中没有这个变量。

您所看到的错误正是它的含义。 @space为nil，您正在呼叫@space.id;由于NilClass没有方法id，因此会抛出错误。

如果你有一个定义该变量的钩子，请在

中编辑该代码

has_many，through：undefined method`id＆＃39;为零：NilClass

1 个答案: