Rails 3 - Truncate in a Controller?

I开发者_运维问答n my controller, I'm building a json object for books. I want to show truncate(book.content, 250).

This doesn't work in a rails controller. And given it's a JSON render, I don't use a view. So how does one truncate? I don't want my JSON object to be huge :)!

Thanks.

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You can use many ways to accomplish this. The most conviniet one would be to just include the proper helper in the controller. In this it would be:

class BooksController < ApplicationController
  include ActionView::Helpers::TextHelper
  ...
end

Alternatively you can also create a partial which generates the code you need, for example _truncate.html.erb with proper code:

<%= truncate (@book, :length => 250) %>

And then render it in your view:

result = render_to_string :partial => 'truncate'

Hope this helps.

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You can just call the truncate rails string method.

http://apidock.com/rails/String/truncate

"Once upon a time in a world far far away".truncate(27)

@book.content.truncate(250)

Not 100% sure if you have to include

include ActionView::Helpers::TextHelper