Rails，如何删除has_many中的关联

I Have a scenario, which I am not able to figure out,

我有一个情形，我无法算出来，

Profile      Product
customer1    Iphone
customer2    Iphone

Now customer1 sells his iphone, so i will have to delete the association between customer1 and iphone but not the profile or product. I have an intermediate table for many to many relationship called product_profiles with product_id and profile_id as fields. Hence i need to delete id's from product_profiles table.

现在customer1出售了他的iphone，所以我必须删除customer1和iphone之间的关联，而不是配置文件或产品。我有一个中间表，其中许多关系称为product_profiles，它的product_id和profile_id作为字段。因此，我需要从product_profiles表删除id。

Product model

产品模型

has_many :product_profiles
has_many :profiles, :through => :product_profiles

Profile model

剖面模型

has_many :product_profiles
has_many :products, :through => :product_profiles

Product controller

产品控制器

def destroy

    if ProductProfile.where(:product_id =>  params[:id]).where(:profile_id => ?).destroy //how to get the profile_id from view when clicked on delete button
      redirect_to admin_products_path
      flash[:success] = "Product Successfully Deleted!"
    else
      flash[:error] = "Sorry! Could not complete the request, please try again!"
      redirect_to :action => 'index'
   end  
 end

View file

视图文件

<% @products.each do |b| %>
                <tr>
                    <td><%= @profile.name %></td> 

                    <td>
                    <% b.sub_categories.each do |p| %>
                        <%= p.name + ',' %>
                    <% end %>
                    </td>

                    <td><%= b.name %></td>
                    <td>
                    <%= link_to "<span class='glyphicon glyphicon-edit'></span>".html_safe,  edit_admin_product_path(b) %>
                   </td>
                   <td>
                    <%= link_to "<span class='glyphicon glyphicon-trash'></span>".html_safe, admin_product_path(b), :method => :delete, :title => "Delete Brand", "data-confirm" => "Do you really want to delete?" %>
                  </td>
                    </tr>
                <% end %>

2 个解决方案

#1

You can pass parameters using the second argument of the path helper.

可以使用路径助手的第二个参数传递参数。

<%= link_to "<span class='glyphicon glyphicon-trash'></span>".html_safe, admin_product_path(b, :profile_id => @profile.id), :method => :delete, :title => "Delete Brand", "data-confirm" => "Do you really want to delete?" %>

In your controller you would then be able to access params[:profile_id]

在您的控制器中，您将能够访问params[:profile_id]

#2

product = Product.find_by_id(product_id)
product.product_profiles.delete(product_profile_id)

Delete is not going to destroy your objects only the association between them.

删除不会破坏你的对象，只会破坏它们之间的关联。

Source: http://neyric.com/2007/07/08/how-to-delete-a-many-to-many-association-with-rails/

来源:http://neyric.com/2007/07/08/how-to-delete-a-many-to-many-association-with-rails/

#1