Rails模型未定义方法`order＆＃39;用Paypal

Question

使用Rails完成书籍Agile Web Development 4.我试图通过他们的沙箱API实现Paypal支付。但在创建订单时，order会出现错误。

我有一个错误：未定义的方法order

class Order < ActiveRecord::Base
  PAYMENT_TYPES = [ "Check", "Credit card", "Purchase order" ]
  has_many :line_items, dependent: :destroy
  # ...
  validates :name, :address, :email, presence: true
  validates :pay_type, inclusion: PAYMENT_TYPES
  def add_line_items_from_cart(cart)
    cart.line_items.each do |item|
      item.cart_id = nil
      line_items << item
      puts line_items
    end
  end

  serialize :notification_params, Hash
  def paypal_url(return_path)
    values = {
        business: "imanov123-facilitator@gmail.com",
        cmd: "_xclick",
        upload: 1,
        return: "#{Rails.application.secrets.app_host}#{return_path}",
        invoice: id,
        amount: order.line_items.price,
        item_name: order.line_items.product.title,
        item_number: order.line_items.id,
        quantity: order.line_items.quantity,
        notify_url: "#{Rails.application.secrets.app_host}/hook"
    }
    "#{Rails.application.secrets.paypal_host}/cgi-bin/webscr?" + values.to_query
  end

end

来自我的订单控制器

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

    respond_to do |format|
      if @order.save
        Cart.destroy(session[:cart_id])
        session[:cart_id] = nil
        OrderNotifier.received(@order).deliver
        format.html { redirect_to @order.paypal_url(order_path(@order)), notice: 
          'Thank you for your order.' }
      else
        format.html { render action: 'new' }
      end
    end
  end

NameError (undefined local variable or method `order' for #<Order:0xb59cca4c>):
  app/models/order.rb:23:in `paypal_url'
  app/controllers/orders_controller.rb:59:in `block (2 levels) in create'
  app/controllers/orders_controller.rb:54:in `create'

Answer 1

您需要在self上调用属性，因为paypal_url是Order类对象上的实例方法，而您的@order变量恰好是：{ {1}}。 @order = Order.new(order_params)方法确实没有order变量。

paypal_url