Module | ActionView::Helpers::TextHelper
In: | lib/action_view/helpers/text_helper.rb

The TextHelper Module provides a set of methods for filtering, formatting and transforming strings that can reduce the amount of inline Ruby code in your views. These helper methods extend ActionView making them callable within your template files as shown in the following example which truncates the title of each post to 10 characters.

      <% @posts.each do |post| %>
        # post == 'This is my title'
        Title: <%= truncate(post.title, 10) %>
      <% end %>
       => Title: This is my...

### Methods

auto_link concat cycle excerpt highlight markdown pluralize reset_cycle sanitize simple_format strip_links strip_tags textilize textilize_without_paragraph truncate word_wrap

### Constants

VERBOTEN_TAGS | = | %w(form script plaintext) unless defined?(VERBOTEN_TAGS)
VERBOTEN_ATTRS | = | /^on/i unless defined?(VERBOTEN_ATTRS)

AUTO_LINK_RE

=

%r{ ( # leading text <\w+.*?>| # leading HTML tag, or [^=!:'"/]| # leading punctuation, or ^ # beginning of line ) ( (?:https?://)| # protocol spec, or (?:www\.) # www.* ) ( [-\w]+ # subdomain or domain (?:\.[-\w]+)* # remaining subdomains or domain (?::\d+)? # port (?:/(?:(?:[~\w\+%-]|(?:[,.;:][^\s$]))+)?)* # path (?:\?[\w\+%&=.;-]+)? # query string (?:\#[\w\-]*)? # trailing anchor ) ([[:punct:]]|\s|<|$) # trailing text }x unless const_defined?(:AUTO_LINK_RE)

### Public Instance methods

auto_link(text, link = :all, href_options = {}, &block)

Turns all urls and email addresses into clickable links. The `link` parameter will limit what should be linked. You can add html attributes to the links using `href_options`. Options for `link` are `:all` (default), `:email_addresses`, and `:urls`.

      auto_link("Go to http://www.rubyonrails.org and say hello to david@loudthinking.com") =>
        Go to <a href="http://www.rubyonrails.org">http://www.rubyonrails.org</a> and
        say hello to <a href="mailto:david@loudthinking.com">david@loudthinking.com</a>

If a block is given, each url and email address is yielded and the result is used as the link text.

      auto_link(post.body, :all, :target => '_blank') do |text|
        truncate(text, 15)
      end

concat(string, binding)

The preferred method of outputting text in your views is to use the <%= "text" %> eRuby syntax. The regular puts and print methods do not operate as expected in an eRuby code block. If you absolutely must output text within a code block, you can use the concat method.

      <% concat "hello", binding %>

is equivalent to using:

      <%= "hello" %>

cycle(first_value, *values)

Creates a Cycle object whose to_s method cycles through elements of an array every time it is called. This can be used for example, to alternate classes for table rows:

      <% @items.each do |item| %>
        <tr class="<%= cycle("even", "odd") -%>">
          <td>item</td>
        </tr>
      <% end %>

You can use named cycles to allow nesting in loops. Passing a Hash as the last parameter with a `:name` key will create a named cycle. You can manually reset a cycle by calling reset_cycle and passing the name of the cycle.

      <% @items.each do |item| %>
        <tr class="<%= cycle("even", "odd", :name => "row_class")
          <td>
            <% item.values.each do |value| %>
              <span style="color:<%= cycle("red", "green", "blue", :name => "colors") -%>">
                value
              </span>
            <% end %>
            <% reset_cycle("colors") %>
          </td>
       </tr>
     <% end %>

excerpt(text, phrase, radius = 100, excerpt_string = "...")

Extracts an excerpt from `text` that matches the first instance of `phrase`. The `radius` expands the excerpt on each side of `phrase` by the number of characters defined in `radius`. If the excerpt radius overflows the beginning or end of the `text`, then the `excerpt_string` will be prepended/appended accordingly. If the `phrase` isn‘t found, nil is returned.

      excerpt('This is an example', 'an', 5)
       => "...s is an examp..."

      excerpt('This is an example', 'is', 5)
       => "This is an..."

highlight(text, phrase, highlighter = '<strong class="highlight">\1</strong>')

Highlights `phrase` everywhere it is found in `text` by inserting it into a `highlighter` string. The highlighter can be specialized by passing `highlighter` as a single-quoted string with \1 where the phrase is to be inserted.

      highlight('You searched for: rails', 'rails')
       => You searched for: <strong class="highlight">rails</strong>

markdown(text)

Returns the text with all the Markdown codes turned into HTML tags. This method is only available if BlueCloth is available.

pluralize(count, singular, plural = nil)

Attempts to pluralize the `singular` word unless `count` is 1. If `plural` is supplied, it will use that when count is > 1, if the ActiveSupport Inflector is loaded, it will use the Inflector to determine the plural form, otherwise it will just add an ‘s’ to the `singular` word.

      pluralize(1, 'person')  => 1 person
      pluralize(2, 'person')  => 2 people
      pluralize(3, 'person', 'users')  => 3 users

reset_cycle(name = "default")

Resets a cycle so that it starts from the first element the next time it is called. Pass in `name` to reset a named cycle.

sanitize(html)

Sanitizes the `html` by converting <form> and <script> tags into regular text, and removing all "onxxx" attributes (so that arbitrary Javascript cannot be executed). It also removes href= and src= attributes that start with "javascript:". You can modify what gets sanitized by defining VERBOTEN_TAGS and VERBOTEN_ATTRS before this Module is loaded.

      sanitize('<script> do_nasty_stuff() </script>')
       => &lt;script> do_nasty_stuff() &lt;/script>
      sanitize('<a href="javascript: sucker();">Click here for $100</a>')
       => <a>Click here for $100</a>

simple_format(text)

Returns `text` transformed into HTML using simple formatting rules. Two or more consecutive newlines(`\n\n`) are considered as a paragraph and wrapped in `<p>` tags. One newline (`\n`) is considered as a linebreak and a `<br />` tag is appended. This method does not remove the newlines from the `text`.

strip_links(text)

Strips link tags from `text` leaving just the link label.

      strip_links('<a href="http://www.rubyonrails.org">Ruby on Rails</a>')
       => Ruby on Rails

strip_tags(html)

Strips all HTML tags from the `html`, including comments. This uses the html-scanner tokenizer and so its HTML parsing ability is limited by that of html-scanner.

textilize(text)

Returns the text with all the Textile codes turned into HTML tags. This method is only available if RedCloth is available.

textilize_without_paragraph(text)

Returns the text with all the Textile codes turned into HTML tags, but without the bounding <p> tag that RedCloth adds. This method is only available if RedCloth is available.

truncate(text, length = 30, truncate_string = "...")

If `text` is longer than `length`, `text` will be truncated to the length of `length` and the last three characters will be replaced with the `truncate_string`.

      truncate("Once upon a time in a world far far away", 14)
       => Once upon a...

word_wrap(text, line_width = 80)

Wraps the `text` into lines no longer than `line_width` width. This method breaks on the first whitespace character that does not exceed `line_width`.

      word_wrap('Once upon a time', 4)
       => Once\nupon\na\ntime

[Validate]