Module

ActionView::Helpers::TagHelper

Inheritance
Included Modules
ERB::Util

Provides methods to generate HTML tags programmatically when you can‘t use a Builder. By default, they output XHTML compliant tags.

Constants

Name   Description
BLOCK_CALLED_FROM_ERB = 'defined? __in_erb_template'
BOOLEAN_ATTRIBUTES = %w(disabled readonly multiple checked).to_set

Methods

Instance

Visibility Signature
public cdata_section (content)
public content_tag (name, content_or_options_with_block = nil, options = nil, escape = true, &block)
public escape_once (html)
public tag (name, options = nil, open = false, escape = true)

Instance Method Detail

cdata_section(content)

Returns a CDATA section with the given content. CDATA sections are used to escape blocks of text containing characters which would otherwise be recognized as markup. CDATA sections begin with the string <![CDATA[ and end with (and may not contain) the string ]]>.

Examples

  cdata_section("<hello world>")
  # => <![CDATA[<hello world>]]>

  cdata_section(File.read("hello_world.txt"))
  # => <![CDATA[<hello from a text file]]>

content_tag(name, content_or_options_with_block = nil, options = nil, escape = true, &block)

Returns an HTML block tag of type name surrounding the content. Add HTML attributes by passing an attributes hash to options. Instead of passing the content as an argument, you can also use a block in which case, you pass your options as the second parameter. Set escape to false to disable attribute value escaping.

Options

The options hash is used with attributes with no value like (disabled and readonly), which you can give a value of true in the options hash. You can use symbols or strings for the attribute names.

Examples

  content_tag(:p, "Hello world!")
   # => <p>Hello world!</p>
  content_tag(:div, content_tag(:p, "Hello world!"), :class => "strong")
   # => <div class="strong"><p>Hello world!</p></div>
  content_tag("select", options, :multiple => true)
   # => <select multiple="multiple">...options...</select>

  <% content_tag :div, :class => "strong" do -%>
    Hello world!
  <% end -%>
   # => <div class="strong">Hello world!</div>

escape_once(html)

Returns an escaped version of html without affecting existing escaped entities.

Examples

  escape_once("1 < 2 &amp; 3")
  # => "1 &lt; 2 &amp; 3"

  escape_once("&lt;&lt; Accept & Checkout")
  # => "&lt;&lt; Accept &amp; Checkout"

tag(name, options = nil, open = false, escape = true)

Returns an empty HTML tag of type name which by default is XHTML compliant. Set open to true to create an open tag compatible with HTML 4.0 and below. Add HTML attributes by passing an attributes hash to options. Set escape to false to disable attribute value escaping.

Options

The options hash is used with attributes with no value like (disabled and readonly), which you can give a value of true in the options hash. You can use symbols or strings for the attribute names.

Examples

  tag("br")
  # => <br />

  tag("br", nil, true)
  # => <br>

  tag("input", { :type => 'text', :disabled => true })
  # => <input type="text" disabled="disabled" />

  tag("img", { :src => "open & shut.png" })
  # => <img src="open &amp; shut.png" />

  tag("img", { :src => "open &amp; shut.png" }, false, false)
  # => <img src="open &amp; shut.png" />