导轨4：增量重复项目

Question

想要在我的购物应用程序中增加重复的项目 因此，当用户下订单然后想要编辑订单时，他可以更改订单数量。

在当我点击量瞬间（我已经设置了数量为1），它进入到order_itmes编辑画面 - 它可以让我更新的顺序，但是当我点击提交后得到一个错误

NameError在OrderItemsController＃更新

@order_item = OrderItem.find(params[:id]) 
    respond_to do |format| 
     if order_item.params[:quantity].to_i == 0 **<-----Error** 
     @order_item.destroy 
     format.html { redirect_to @order_item.order, notice: 'Item was deleted from your cart.' } 
     format.json { head :no_content } 

参数

{"utf8"=>"✓", 
"_method"=>"patch", 
"authenticity_token"=>"/8xRjbtusgdLV5SVQP55aUDccYdUzB9G23heTtEeNfk=", 
"order_item"=>{"quantity"=>"2"}, 
"commit"=>"Update Order item", 
"id"=>"68"} 

ORDER_ITEMS控制器

class OrderItemsController < ApplicationController 
    before_action :set_order_item, only: [:show, :edit, :destroy] 
    before_action :load_order, only: [:create] 


    # GET /order_items/1/edit 
    def edit 
    end 

    # POST /order_items 
    # POST /order_items.json 
    def create 
     @order_item = @order.order_items.find_or_initialize_by_product_id(params[:product_id]) 
     @order_item.quantity += 1 

    respond_to do |format| 
     if @order_item.save 
     format.html { redirect_to @order, notice: 'Successfully Added Product To Cart.' } 
     format.json { render action: 'show', status: :created, location: @order_item } 
     else 
     format.html { render action: 'new' } 
     format.json { render json: @order_item.errors, status: :unprocessable_entity } 
     end 
    end 
    end 

    # PATCH/PUT /order_items/1 
    # PATCH/PUT /order_items/1.json 
    def update 
    @order_item = OrderItem.find(params[:id]) 
    respond_to do |format| 
     if order_item.params[:quantity].to_i == 0 
     @order_item.destroy 
     format.html { redirect_to @order_item.order, notice: 'Item was deleted from your cart.' } 
     format.json { head :no_content } 
     elsif @order_item.update(order_item_params) 
     format.html { redirect_to @order_item.order, notice: 'Successfully updated the order item.' } 
     else 
     format.html { render action: 'edit' } 
     format.json { render json: @order_item.errors, status: :unprocessable_entity } 
     end 
    end 
    end 

    # DELETE /order_items/1 
    # DELETE /order_items/1.json 
    def destroy 
    @order_item.destroy 
    respond_to do |format| 
     format.html { redirect_to @order_item.order } 
     format.json { head :no_content } 
    end 
    end 

    private 
    # Use callbacks to share common setup or constraints between actions. 
    def set_order_item 
     @order_item = OrderItem.find(params[:id]) 
    end 

    def load_order 
     @order = Order.find_or_initialize_by_id(session[:order_id], status: "Unsubmitted", user_id: session[:user_id]) 

     if @order.new_record? 
      @order.save! 
      session[:order_id] = @order.id 
     end 
    end 

    # Never trust parameters from the scary internet, only allow the white list through. 
    def order_item_params 
     params.require(:order_item).permit(:product_id, :order_id, :quantity) 
    end 
end 

order.controller

class OrdersController < ApplicationController 
    before_action :set_order, only: [:show, :edit, :update, :destroy, :confirm] 

    # GET /orders 
    # GET /orders.json 
    def index 
    @orders = Order.all 
    end 

    # GET /orders/1 
    # GET /orders/1.json 
    def show 
    end 

    # GET /orders/new 
    def new 
    @order = Order.new 
    end 

    # GET /orders/1/edit 
    def edit 
    end 

    # POST /orders 
    # POST /orders.json 
    def create 
    @order = Order.new(order_params) 

    respond_to do |format| 
     if @order.save 
     format.html { redirect_to @order, notice: 'Order was successfully created.' } 
     format.json { render action: 'show', status: :created, location: @order } 
     else 
     format.html { render action: 'new' } 
     format.json { render json: @order.errors, status: :unprocessable_entity } 
     end 
    end 
    end 

    # PATCH/PUT /orders/1 
    # PATCH/PUT /orders/1.json 
    def update 
    respond_to do |format| 
     if @order.update(order_params.merge(status: 'submitted')) 
     format.html { redirect_to confirm_order_path(@order), notice: 'Order was successfully updated.' } 
     format.json { head :no_content } 
     else 
     format.html { render action: 'edit' } 
     format.json { render json: @order.errors, status: :unprocessable_entity } 
     end 
    end 
    end 

    # DELETE /orders/1 
    # DELETE /orders/1.json 
    def destroy 
    @order.destroy 
    respond_to do |format| 
     format.html { redirect_to products_path } 
     format.json { head :no_content } 
    end 
    end 

    def confirm 
    end 

    private 
    # Use callbacks to share common setup or constraints between actions. 
    def set_order 
     @order = Order.find(params[:id]) 
    end 

    # Never trust parameters from the scary internet, only allow the white list through. 
    def order_params 
     params.require(:order).permit(:user_id, :status, :address_id) 
    end 
end 

order_item.rb

class OrderItem < ActiveRecord::Base 

    belongs_to :order 
    belongs_to :product 

    validates :order_id, :product_id, presence: true 
    validates :quantity, numericality: { only_integer: true, greater_than: 0 } 

    def subtotal 
    quantity * product.price 
    end 
end 

Answer 1

刚刚看到它，如果order_item.params [：量] .to_i == 0

应如果order_item_params [：quantity] .to_i == 0