Ruby on Rails外键

Question

basically what I am trying to do is use a foreign key. Eg 144 which will return an object. I keep getting an error saying the record number cannot be found.

In the order show view.

(I have tested it and @order.cart_id is valid and does return a number. Eg 144

<b>Order items:</b>
<%= @cart.get_order_cart(@order.cart_id) %>

In cart model, get_order_cart method

def get_order_cart(cart_id)
  cart = Cart.find(cart_id)
  cart.line_items.each do |item| 
    item.product.title
  end
end

Like I say though, this doesn't work. What is the problem please? Thanks

Answer 1

Why don't you use ActiveRecord associations?

class Order < ActiveRecord::Base
  belongs_to :cart
end

class Cart < ActiveRecord::Base
  has_many :orders
end

Now, you can get your cart simply by

@cart = @order.cart