Is there an HTML safe truncate method in Rails?

the regular truncate function works fine, just pass :escape => false as an option to keep the HTML intact. eg:

truncate(@html_text, :length => 230, :omission => "" , :escape => false)

RubyOnRails.org

*Edit I didn't read the question very carefully (or at all TBH), so this answer does not solve this question... It IS the answer I happened to be looking for though, so hopefully it helps 1 or 2 people :)

There are two completely different solutions both with the same name: truncate_html

1. https://github.com/ianwhite/truncate_html : This is a gem and uses an html parser (nokogiri)
2. https://github.com/hgmnz/truncate_html : This is a file you put in your helpers directory. It uses regular expressions and has no dependencies.

You should solve this problem with CSS rather than Ruby. You are doing something that affects the DOM layout, and there is no way to programmatically devise a solution that will work consistently.

Let's say you get your HTML parser gem working, and you find a lowest common denominator character count that will work most of the time.

What happens if you change font sizes, or your site layout? You'll have to recalculate the character count again.

Or let's say your html has something like this in it: <p><br /></p><br /> That is zero characters, however it would cause a big chunk of blank text to be inserted. It could even be a <blockquote> or <code> tag with too much padding or margin to throw your layout totally out of whack.

Or the inverse, let's say you have this 3 ≅ λ (3 ≅ λ) That is 26 characters long, but for display purposes it is only 5.

The point being that character count tells you nothing about how something will render in the browser. Not to mention the fact HTML parsers are hefty pieces of code that can at times be unreliable.

Here is some good CSS to deal with this. The :after pseudo class will add a white fade to the last line of content. Very nice transition.

body { font-size: 16px;}p {font-size: 1em; line-height: 1.2em}/* Maximum height math is:   line-height * #oflines - 0.4   the 0.4 offset is to make the cutoff  look nicer */.lines-3{height: 3.2em;}.lines-6{height: 6.8em;}.truncate {overflow: hidden; position:relative}.truncate:after{    content:"";     height: 1em;     display: block;     width: 100%;     position:absolute;    background-color:white;     opacity: 0.8;     bottom: -0.3em}

You can add as many .lines-x classes as you see fit. I used em but px is just as good.

Then apply this to your element: <div class="truncate lines-3">....lots of stuff.. </div>

and the fiddle: http://jsfiddle.net/ke87h/