HTML and Ruby on Rails - Display <br/> tags as line breaks, but other tags as strings

Question

I'm working on my first Rails website, but I have a little problem: I want to display the <br/> tags as line breaks, but I also want to display the other tags as strings.

For example, the user input is:

<a href='#2'>Go to #2</a><br/><a href='#3'>Go to #3</a>

I want to display:

<a href='#2'>Go to #2</a>
<a href='#3'>Go to #3</a>

I know that I can display the <br/> tags as line breaks like this:

<%= simple_format @user_input %>

But the problem is that this command display:

Go to #2
Go to #3

And not:

<a href='#2'>Go to #2</a>
<a href='#3'>Go to #3</a>

Thank you in advance!

Answer 1

Use the Rails sanitize helper method and whitelist the tags you want to allow and leave those out that you don't. All those left out would be stripped and shown as text. So in your case it would be something like

<%= sanitize @user_input, tags: %w(br) %>

For the sanitize method api info see http://api.rubyonrails.org/classes/ActionView/Helpers/SanitizeHelper.html#method-i-sanitize.