rendering a partial Rails3.x + coffeescript - ruby-on-rails-3

Question

I have the following requirement. I have a 'school' drop down and as the last options I have add new school, so if the user selects that option I want to load the new_school form as a partial via ajax.
I'm on
gem 'rails', '3.2.9'
gem 'coffee-rails', '~> 3.2.1'
Jquery via gem 'jquery-rails'
Earlier with rails < 3 and prototype I used to do it with
Ajax.Updater (aka Rails link_to_remote :update => 'some_div')
and with rails > 3 + JQuery I'm familiar with *.js.erb, and having something like
$("#school_form").html("<%= escape_javascript(render(:partial => "form"))%>");
But I'm new to coffeescript and I have no idea on how to do this with coffeescript, can someone help me :), (because I believe you shouldn't have to do a server request for this)
So far I have done following to catch the select_tag change event
$ ->
$('#school_name_select').change ->
unless $(this).val()
$('school_name').html([I want to have the _new_school_form partial here])

Answer 1

Use a hidden div.
In general, you don't want to bother trying to mix JS and HTML. The escaping can be complicated, error-prone, and flat out dangerous due to the possibility of cross-site scripting attacks.
Simply render your form partial in a div that's not displayed by default. In ERB:
<div id="school_name_form" style="display: none;">
<%= render 'form' %>
</div>
In your CoffeeScript:
$ ->
$('#school_name_select').change ->
if $(this).val()
$('#school_name_form').slideUp()
else
$('#school_name_form').slideDown()
I recommend using a small, tasteful transition like slide or fade. It gives your app a more polished feel.
No AJAX is required. This pattern is so common that I have an application-wide style defined as follows.
.not-displayed {
display: none;
}
Then using HAML (if you're into that), the HTML template becomes simply:
#school_name_form.not-displayed
= render 'form'

Answer 2

You can try to render the form partial inside hidden div (not too correct from semantic point of view), or put the form html as data attribute of any relevant element, something like
f.select school_name, ... , data: {form: escape_javascript(render(:partial => "form"))}
And the Coffeescript
$ ->
$('#school_name_select').change ->
unless $(this).val()
$('school_name').html($('#school_name_select').data('form'))