Ruby on Rails javascript assets

Question

I have a problems with javascripts assets in Ruby on Rails. Descripttion: I have two files in app/assets/javascript folder.

1. "constans.js" include a constant array "var FEATURES = new Array["A","B","C"]"
2. "route.js.erb" <%= FEATURES[1] %>

Now , I'm implementing my function in "route.js.erb" but I can't access the "FEATURES" array ?
I searched on Google but can't not find the solution.
So, anybody can help me? Thanks! ( my first question in stack overflow , sorry for my bad english)

Answer 1

use

window.FEATURES = new Array["A","B","C"]"

in constants.js

and make sure that the constants.js is being loaded.

Answer 2

There are several important factors:

1. Scoping of the variable
2. Calling the variable in ERB

Scope

First, you need to ensure your variable is scoped globally. To do this, you've declared the variable in constants.js , so you need to ensure this is called before the routes.js.erb file. You should also take @user3243476 's advice & append it to the window object:

#js/constants.js
window.FEATURES = new Array["A","B","C"]

---

ERB

Secondly, you're calling routes.js.erb (which is fine), but inside you're calling <%= FEATURES["1"] %> . Problem. This is calling a Rails constant, not the JS one. This means even if your variable's scope is global, you're trying to call one which doesn't exist.

You'll need to do this:

#js/routes.js.erb
alert(FEATURES["1"]);