How to replace Space with Line Break in Ruby on Rails? - ruby-on-rails

Question

I am trying to replace Space in a string with Line Break in Ruby on Rails,
name = 'john smith'
i have tried the following so far:
name.gsub!(" ", "\n")
name.gsub!(" ", "<br>")
name.sub(" ", "\n")
name.sub(" ", "<br>")
but none of the above worked.

Answer 1

You have to be careful when marking a string as html_safe, especially if it may contain user input:
name = 'john smith<script>alert("gotcha")</script>'
name.gsub(' ', '<br>').html_safe
#=> "john<br>smith<script>alert(\"gotcha\")</script>"
Rails would output that string as-is, i.e. including the <script> tag.
In order to take advantage of Rails' HTML escaping, you should only mark the trusted parts as being html_safe. For a manually concatenated string:
''.html_safe + 'john' + '<br>'.html_safe + 'smith<script>alert("gotcha")</script>'
#=> "john<br>smith<script>alert("gotcha")</script>"
As you can see, only the <br> tag was left intact, the remaining parts were properly escaped.
There are several helpers for building safe strings as well as for building HTML tags. In your case, I'd use safe_join and tag:
name = 'john smith<script>alert("gotcha")</script>'
safe_join(name.split(' '), tag(:br))
#=> "john<br />smith<script>alert("gotcha")</script>"

Answer 2

While printing it in html you will need to use raw, otherwise rails will escape the tags
= raw name.gsub(" ", "<br>")

Answer 3

Try another one:
<%= name.gsub(" ", "<br>").html_safe %>
html_safe :
Marks a string as trusted safe. It will be inserted into HTML with no additional escaping performed.
"<a>Hello</a>".html_safe
#=> "<a>Hello</a>"
nil.html_safe
#=> NoMethodError: undefined method `html_safe' for nil:NilClass
raw :
raw is just a wrapper around html_safe. Use raw if there are chances that the string will be nil.
raw("<a>Hello</a>")
#=> "<a>Hello</a>"
raw(nil)
#=> ""