How to pass a variable from javascript (coffeescript) to rails controller?

Question

I guess this should be simple, but I can't figure it out

I my view there is a link that I want to trigger some ajax:

link_to( "#{sir.sir_id}" , '#', :data => {'sir-id' => sir.id}, remote: true ),

In my coffeescript I can get the value of the data-attribute in the link like so:

$ ->
  $("a[data-sir-id]").click ->
  data_sir_id = $(this).data("sir-id")

So I need the value of that variable (data_sir_id) in my controller, so I can get its associated model objects and render them in the same view

How could I achieve that?

Answer 1

You don't need to store your data in a data attribute and to make an ajax call when clicking on the link: link_to provides you a great way to make link and to pass parameters.

And by using, remote: true , it will do an ajax call without any other configuration.

link_to("#{sir.sir_id}", path_to_the_controller_action(sir_id: sir.id), remote: true)

Then, in your controller action, your data will be accessible in params[:sir_id]

Answer 2

Here in link_to you have passed url as '#' , so if you have a particular action that you can add then you can go by above way

else you can use the following:

To specify link in view, you can use it as

link_to "#{sir.sir_id}", '#', remote: true, 'sir-id' => sir.id, class: 'sir_id_link'

In coffeescript:

$ ->
  $("sir_id_link").live "click", ->
  data_sir_id = $(@).attr("sir-id")
  $.ajax
    url: any_url
    type: "PUT"
    data:
      sir_id: data_sir_id
    success: (data) ->
      ...

Now in your controller action, you can access it as params[:sir_id].

Hope this would help you.

Thanks.