在Rails中向业务模型添加多个类别

Question

我正在尝试设置一个rails应用程序，该应用程序具有业务模型和类别模型。一个业务可以有多个类别，并且这些类别可以属于多个业务。

一切似乎都正常工作，我没有收到任何错误，除了试图显示与特定业务相关的类别时，没有显示任何内容。

以下是我的模型、控制器和视图。这是我的第一个rails项目，我正在寻求一些帮助。

business.rb

class Business < ActiveRecord::Base
  attr_accessible :category_id
  belongs_to :category
end

类别.rb

class Category < ActiveRecord::Base
  attr_accessible :name, :description
  has_many :businesses
end

business_controller.rb

def show
  @business = Business.find(params[:id])
  @categories = Category.where(:business_id => @business).all
  respond_to do |format|
    format.html # show.html.erb
    format.json { render json: @business }
  end
end
def new
  @business = Business.new
  @categories = Category.order(:name)
  respond_to do |format|
    format.html # new.html.erb
    format.json { render json: @business }
  end
end
def edit
  @business = Business.find(params[:id])
  @categories = Category.order(:name)
end

business_form.html.erb

...
<div class="field">
    <%= f.association :category, input_html: { class: 'chosen-select', multiple: true } %>
</div>
...

business/show.html.erb

...
<ul class="tags">
  <% @categories.each do |category| %>
    <li><%= category.name %></li>
  <% end %>
</ul>
...

Answer 1

考虑到您希望一个企业有许多类别，您的模型的关系应该更新如下：

业务

def Business < ActiveRecord::Base
  has_many :categories
  attr_accessible :name, :etc
  # attr_accessible :category_id would not apply as the business model 
  # would not have this relationship
end

类别

def Category < ActiveRecord::Base
  attr_accessible :business_id, :name, :description
  belongs_to :business
end

然后，在您的控制器中，您可以访问数据：

业务控制器

def show
  @business = Business.find(params[:id])
  @categories = @business.categories 
  respond_to ... 
end