appending <a href> to keywords in rails

Question

Basically, there are some keywords that i want to pick out and assign a link to them dynamically.

How should i go about in doing this?

Let's say i have something like this;

<p>ruby, rails, php, python, django and sinatra</p>

and i would like to assign links to keywords like ruby and python, so the end results should look like this;

<p><a href="http://www.ruby-lang.org"&gt;ruby&lt;/a&gt;, rails, php, <a href="http://www.python.org"&gt;python&lt;/a&gt;, django and sinatra</p>

Any help or suggestion would be much appreciated!

Answer 1

Simply use text replacement? Replace "ruby" with "<a href="http://ruby-lang.org">ruby&lt;/a>", and done. See the String.replace in the javascript reference .

Answer 2

If you want to do it on the server side before the content is rendered to the browser then you can do it like

str = "<p>ruby, rails, php, python, django and sinatra scruby rubysd 12ruby'; ruby </p>"

link_hash = {'ruby' => "<a href = 'http://www.ruby-lang.org'&gt;ruby&lt;/a&gt;", 'python' => "<a href='http://www.python.org'&gt;python&lt;/a&gt;" }

link_hash.each_pair do |key, value|
  str = str.gsub(/\b#{key}\b/, value)
end

str #=> "<p><a href = 'http://www.ruby-lang.org'&gt;ruby&lt;/a&gt;, rails, php, <a href='http://www.python.org'&gt;python&lt;/a&gt;, django and sinatra scruby rubysd 12ruby'; <a href = 'http://www.ruby-lang.org'&gt;ruby&lt;/a&gt; </p>"

Answer 3

If you wanted to be particularly fancy, I think you could use an after filter:

class MyController < ApplicationController
  after_filter :link_stuff

  protected

  def link_stuff
    # You'd want to do this more carefully, so as to only get "ruby"s in text, 
    # not in tags etc.
    response.body.gsub(/ruby/, "<a href = 'http://www.ruby-lang.org'&gt;ruby&lt;/a&gt;")
  end
end

Answer 4

One way of doing it, assuming you only want to link whole words:

html = "<p>ruby, rails, php, python, django and sinatra</p>"

word_links = { "ruby"   => "http://www.ruby-lang.org",
               "python" => "http://www.python.org" }

html.gsub(/\w+/) do |word|
  word_links[word] ? "<a href=\"#{word_links[word]}\">#{word}</a>" : word
end

If the text you are operating on is rather large, but the list of words you want to link is pretty small, this may be optimized a little by doing substitution on matching words only:

html.gsub(/\b(#{word_links.keys.join('|')})\b/,
          "<a href=\"#{word_links[$1]}\">#{$1}</a>")

Just make sure you don't have any keywords that can appear inside an opening tag (like inside an attribute value for example, which would break completely with this solution.) For a truly robust solution you will have to use a proper HTML parser and just replace content text.

Answer 5

Hi

You can do like this

first get the values as an array (or list) Ex: ruby php python etc..

send this array to a helper

def link_builder(arr) html_string = ""

for element in arr

 check whether your word needs a wrapper. you might want to do a table check 

 if warpper_needed?

    html_string = html_string + <a href='link'>elment</a>
 else
    html_string = html_string + <p>element</p>
 end

end

html_string

end

Hope you got the idea, (this might not work as it is)

cheers, sameera