pass parameter by link_to ruby on rails

Question

I have this line of code:

<%= link_to "Add to cart", :controller => "car", :action => "add_to_cart", :car => car %>

when im in the add_to_cart method...how can i call the :car please?

@car = Car.new(params[:car])

That doesn't work because it says that I'm trying to stringify it.

I don't understand what's wrong; because I used this to create new users and it worked fine.

By the way, car is my car object.

score 141 · Accepted Answer · edited Dec 26 '22 at 03:33

141

Try:

<%= link_to "Add to cart", {:controller => "car", :action => "add_to_cart", :car => car.id }%>

and then in your controller

@car = Car.find(params[:car])

which, will find in your 'cars' table (as with rails pluralization) in your DB a car with id == to car.id

edited Dec 26 '22 at 03:33

starball

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answered Aug 05 '11 at 04:36

juanm55

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2

But what if the parameter depends on, let's say, the value of an input, which may be dynamic in nature? – Sebastialonso Mar 17 '14 at 23:12

score 80 · Answer 2 · edited Jun 19 '15 at 17:41

80

The above did not work for me but this did

<%= link_to "text_to_show_in_url", action_controller_path(:gender => "male", :param2=> "something_else") %>

edited Jun 19 '15 at 17:41

Arslan Ali

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answered Jul 26 '11 at 07:09

Jonathan Leung

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score 7 · Answer 3 · answered Dec 14 '09 at 04:06

Maybe try this:

<%= link_to "Add to cart", 
            :controller => "car", 
            :action => "add_to_cart", 
            :car => car.attributes %>

But I'd really like to see where the car object is getting setup for this page (i.e., the rest of the view).

score 2 · Answer 4 · answered Dec 14 '09 at 03:27

2

You probably don't want to pass the car object as a parameter, try just passing car.id. What do you get when you inspect(params) after clicking "Add to cart"?

answered Dec 14 '09 at 03:27

bensie

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the problem with that is that I don't have these cars saved anywhere since I'm scraping the informatin from the web and am not storing them anywhere..thus the id is non-existent as yet and apart from that would be useless :/ – Lilz Dec 14 '09 at 03:32
Once again, what do you get when you inspect(params)? – bensie Dec 14 '09 at 03:37
1

params[:product].inspect came back empty "" – Lilz Dec 14 '09 at 03:46
if you don't have an 'id' what do you expect to become a parameter? – Dmytrii Nagirniak Dec 14 '09 at 04:03

pass parameter by link_to ruby on rails

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