Question

我刚开始使用rails并在rails应用程序上工作，我一直在思考这个问题。

我有三个模特

class Product < ActiveRecord::Base

    attr_accessible :name, :issn, :category, :user_products_attributes

    validates_presence_of :name, :issn, :category
    validates_numericality_of :issn, :message => "has to be a number"

    has_many :user_products
    has_many :users, :through => :user_products

    accepts_nested_attributes_for :user_products

end




class UserProduct < ActiveRecord::Base

  attr_accessible :price, :category

  validates_presence_of :price, :category
  validates_numericality_of :price, :message => "has to be a number"

  belongs_to :user
  belongs_to :product

end

class user < ActiveRecord::Base

  # devise authentication here

  # Setup accessible (or protected) attributes for your model
  attr_accessible :email, :password, :password_confirmation, :remember_me

  has_many :user_products, :dependent => :destroy
  has_many :products, :through => :user_products

end

产品控制器

def new

@product = product.new

@product.user_products.build 

respond_to do |format|
  format.html # new.html.erb
  format.json { render json: @product }
end

端

所以问题是这样的：我希望用户在表单中输入产品的信息，但它还涉及存在与产品相关的不同模型/表（user_product）中存在的产品的价格。我怎样才能做到这一点？您可以看到我的form_for使用@product。

任何帮助将不胜感激。

    <div class="span8">

       <div id="listBoxWrapper">          
        <fieldset>

         <%= form_for(@product, :html => { :class => "form-inline" }, :style => "margin-bottom: 60px" ) do |f| %>


            <div class="control-group">
              <label class="control-label" for="Category">Category</label>
              <div class="controls">

                <%= f.text_field :category, :class => 'input-xlarge', :id => "Category" %>       

              </div>
            </div>

           <div class="control-group" style="display: inline-table;">
           <label class="control-label" for="First Name">Price($/Month)</label>
             <div class="controls">
              <%= product.fields_for :user_products do |p| %>
                <%= p.text_field :price, :class => 'input-xlarge input-name' %>    
                <% end %>
              </div>
            </div>

Answer 1

应该是以下

<%= form_for(@product) do |product| %>
  <%= product.text_field :name, :class => 'input-xlarge input-name' %>
  <%= product.fields_for :user_products do |user_product| %>
      <%= user_product.text_field :price, :class => 'input-xlarge input-name' %>

您需要为控制器中的user_products构建@product。像

@product.user_products.build

并且您的Product模型应具有以下内容

accepts_nested_attributes_for :user_products

这将使其意识到在保存产品实体时可能会出现user_products值。

修改

只是解释嵌套表格的骨架

form_for(@object) do |object_form_builder| # call any field generator helper function by object_form_builder like object_form_builder.text_field object_form_builder.check_box # so on... #Now for nested forms get the nested objects from the builder like object_form_builder.fields_for :nested_objects do |nested_object_builder| #generate the fields for this with nested_object_builder. Like nested_object_builder.text_field # so on... end end

是的，对于对象构建器使用短名称总是很方便，就像通常使用f form_builder一样。

通过关联分配模型的属性

1 个答案: