此应用中任意位置的当前购物车电话

Question

this is index.html.erb
            <p>
             <%= number_to_currency(product.price) %>  
             <%= button_to 'Add to Cart', cart_items_path(:product_id => product) %>
            </p>

cart.rb

class Cart
  include Mongoid::Document
  include Mongoid::Timestamps 
  # references_many :cart_items, :dependent => :destroy
   has_many :cart_items, :dependent => :destroy , :autosave => true 
  # embeds_many :cart_items

  # accepts_nested_attributes_for :cart_items
  # attr_accessible :cart_items_attributes
end

cart_item.rb

class CartItem
  include Mongoid::Document
  include Mongoid::Timestamps 
  # referenced_in :cart
  # embedded_in :cart
  belongs_to :cart
  belongs_to :product 
  # embedded_in :product  
  field :product_id, :type => Integer
  field :cart_id, :type => Integer
  field :quantity, :type => Integer
  field :price, :type => Float
end

application_controller.rb

...

私有

此应用中任意位置的当前购物车电话

def current_cart

cart = if session[:cart_id]
  Cart.find(session[:cart_id])
else
  Cart.create!
end
   session[:cart_id] = cart.id

端

cart_items.rb

... def create

@cart = current_cart 
product = Product.find(params[:product_id]) 
@cart_item = @cart.cart_items.build(:product => product)
# @cart_item = CartItem.new(params[:product => product])
 # @cart_item = CartItem.new(params[:cart_item])

respond_to do |format|
  if @cart_item.save
    format.html { redirect_to(@cart_item,  notice: 'Cart item was successfully created.') }
    format.json { render json: @cart_item, status: :created, location: @cart_item }
  else
    format.html { render action: "new" }
    format.json { render json: @cart_item.errors, status: :unprocessable_entity }
  end
end

端 ....

product.rb

require 'carrierwave/orm/mongoid'
class Product
  include Mongoid::Document
  include Mongoid::Timestamps 
  # include Mongoid::Observing
  # include Mongoid::Tree
  has_many :line_items

  # before_destroy :ensure_not_referenced_by_any_line_item

  field :title, :type => String
  field :description, :type => String
  # field :image, :type => String
  mount_uploader :image, ImageUploader
  field :price, :type => Float
  field :category_id, :type => Integer
  field :stock_level, :type => Integer


  set_callback(:destroy, :before) do |document|
    document.ensure_not_referenced_by_any_line_item
  end

  protected
  def ensure_not_referenced_by_any_line_item        
   if cart_items.empty? 
     return true 
   else
     errors.add(:base, 'Line Items present')
     return false 
    end
   end
end

结果如下： CartItemsController中的 NoMethodError #create BSON :: ObjectId（'4e156c78421aa918eb000005'）的未定义方法`cart_items'：BSON :: ObjectId Rails.root：/ Users / user / railworks / rcart

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参数：

{ “authenticity_token”=＆gt; “中vwNaDytLihv5ev3M2tP5uZBjwR1 / t6ld0iFF1gGwWsw =”， “PRODUCT_ID”=＆gt; “中4e126c01421aa93347000002”} 显示会话转储

_csrf_token：“vwNaDytLihv5ev3M2tP5uZBjwR1 / t6ld0iFF1gGwWsw =” cart_id：BSON :: ObjectId（'4e156c78421aa918eb000005'） session_id：“532c1ca0f48a6fca905a97afba912e05”

我没有得到问题点。为什么会这样未定义的方法`cart_items'??? 感谢。

Answer 1

我需要查看抛出错误的代码，以便为您提供关于错误被抛出的明确答案（即create方法），但为什么不为此尝试购物车创建代码：

def current_cart
  cart = Cart.find_or_create_by(:id => session[:cart_id])
  session[:cart_id] ||= cart.id
  return cart
end

看起来你的当前实现在查找/创建它时实际上并没有返回购物车项目，而是返回session[:cart_id]变量。

另一种更有趣的解决方案可能是将帮助程序拆分为两种方法：

def current_cart_id
  session[:cart_id] ||= Cart.find_or_create_by(:id => session[:cart_id]).id
end

def current_cart
  @current_cart ||= Cart.find(current_cart_id)
end

然后，您可以随时轻松访问current_cart对象及其id。

mongoid has_many关系

cart.rb

cart_item.rb

application_controller.rb

此应用中任意位置的当前购物车电话

cart_items.rb

product.rb

1 个答案: