# Add to cart functionality(getting error)

**URL:** <https://www.ruby-forum.com/t/add-to-cart-functionality-getting-error/121383>\
**Category:** Rails\
**Created:** [November 27, 2007, 2:12pm UTC](https://www.ruby-forum.com/t/add-to-cart-functionality-getting-error/121383 "2007-11-27T14:12:37Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![ror-user](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/22d042/32.png) [@ror-user](https://www.ruby-forum.com/u/ror-user)\
**Post date:** [November 27, 2007, 2:12pm UTC](https://www.ruby-forum.com/t/add-to-cart-functionality-getting-error/121383/1 "2007-11-27T14:12:37Z")

</div>

Hi,

I am implementing shopping cart and getting error in add\_to\_cart.  
The error is:  
ActiveRecord::AssociationTypeMismatch in StoreController#cart

Product expected, got Fixnum

The add\_to\_cart method is:  
def add\_to\_cart  
product = Product.find(params[:id])  
@cart = find\_cart  
@cart.add\_product(product)  
redirect\_to(:action =\>‘display\_cart’)  
rescue  
logger.error(“Attempt to access invalid product #{params[:id]}”)  
flash[:notice] =‘Invalid product’  
redirect\_to(:action =\> ‘index’)  
end

render\_text product.id is giving id of the product.  
Can anyone tell me how to solve it?