Pass a ruby variable into js within Rails

rubyonrails-talk
1

I have a variable created by some ruby in my controller that looks like this:

@begpoint = row["begpoint"]

and I want to pass it into some js that is referenced from within my view:

view:

  <% javascript_include_tag "play_time" %>

js (play_time):

I am trying to pass "<beg-point> into the js [obviously that <> is not the right syntax just trying to denote where'd id like the variable to end up]

var endtime = <beg-point>+10; myPlayer= document.getElementById('example_video_1'); myPlayer.addEventListener('loadeddata', function(){     myPlayer.currentTime = 10505.89;     myPlayer.play();     myPlayer.addEventListener('timeupdate', function(){     if (myPlayer.currentTime >= endtime) {         myPlayer.pause();     }

Can anyone help? Thanks

    }, false);

}, false);

2

Pierre-Andre M. wrote in post #1147586:

I have a variable created by some ruby in my controller that looks like this:

@begpoint = row["begpoint"]

and I want to pass it into some js that is referenced from within my view:

There are several way of doing this, but the simplest is to use HTML5 data- attributes.

Example:

HTML:

<body data-begpoint="<%= @begpoint %>"> ... page content </body>

jQuery:

var begpoint;

$(funtion() {   begpoint = $('body').data('begpoint'); });

So to think of is as "pass it to JavaScript" is sort of inside out. You use JavaScript to "get" the value from the DOM. jQuery gives you nice syntax for doing just that.

This is good for relatively small amount of data. If you need lots of data in your JavaScript there are alternatives to this technique. A good place to learn something about those techniques is something like Backbone.js, Ember.js or Angular.

http://backbonejs.org

3

I’ve used the gon gem for this and liked it quite a bit.

https://github.com/gazay/gon

Pierre-Andre M. wrote:

4

gon is great, and easy to use.