How to pass a javascript variable into a erb code in a js view?

Question

I have this Javascript view in my Rails 3 project:

app/views/expenses/new_daily.js.erb

var i = parseInt($(\'#daily\').attr(\'data-num\')) + 1;
//$(\'         


        

Answer 1

1) You may create a js tag with global variable in you erb template, after that you will be able to access that variable from any js file

<%= javascript_tag do %>
   window.productsURL = '<%= j products_url %>';
<% end %>

2) You can pass data to data-attribute in erb template and access it by js on client side that way $('#products').data('products')

<%= content_tag "div", id: "products", data: {products: Product.limit(10)} do %>
   Loading products...
<% end %>

3) You can use gon, to use your Rails variables in your js

There is a good article, read it and fine solution for your specific case http://railscasts.com/episodes/324-passing-data-to-javascript, more comments are here http://railscasts.com/episodes/324-passing-data-to-javascript?view=asciicast