Dan Rubio Dan Rubio - 11 months ago 39
CoffeeScript Question

Why can't I iterate over this array saved on an html data selector with javascript?

I have an html element in haml that looks like this:

= select_tag 'release_version', options_for_select(major_releases(@releases)), include_blank: 'All', style: 'max-width: 30%', data: { releases: @releases }

variable is an active record relation object with a bunch of release objects.

In my coffeefile, I have this code:

$('#release_version').on 'change', ->
selVal = $('#release_version').val()
release_html_selector = document.getElementById('release_version')
release_objects = release_html_selector.dataset.releases
filtered_releases = release_objects.filter((item) ->
///^#{selVal}///.test item.version

When the code tries to execute I get this error:

application.js:35397 Uncaught TypeError: release_objects.filter is not a function

When I inspect the elements with
the object looks like this:


This is an iterable data structure. Is there something I'm missing here?

Answer Source

It's possible that the data is actually JSON string not array

Try parsing it as json

release_objects = JSON.parse(release_html_selector.dataset.releases)