Module ActionView::Helpers::TagHelper
In: vendor/rails/actionpack/lib/action_view/helpers/tag_helper.rb

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

Methods

Included Modules

ERB::Util

Constants

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

Public Instance methods

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]]>

[Source]

    # File vendor/rails/actionpack/lib/action_view/helpers/tag_helper.rb, line 93
93:       def cdata_section(content)
94:         "<![CDATA[#{content}]]>".html_safe
95:       end

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>

[Source]

    # File vendor/rails/actionpack/lib/action_view/helpers/tag_helper.rb, line 67
67:       def content_tag(name, content_or_options_with_block = nil, options = nil, escape = true, &block)
68:         if block_given?
69:           options = content_or_options_with_block if content_or_options_with_block.is_a?(Hash)
70:           content_tag = content_tag_string(name, capture(&block), options, escape)
71: 
72:           if block_called_from_erb?(block)
73:             concat(content_tag)
74:           else
75:             content_tag
76:           end
77:         else
78:           content_tag_string(name, content_or_options_with_block, options, escape)
79:         end
80:       end

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"

[Source]

     # File vendor/rails/actionpack/lib/action_view/helpers/tag_helper.rb, line 105
105:       def escape_once(html)
106:         ActiveSupport::Multibyte.clean(html.to_s).gsub(/[\"><]|&(?!([a-zA-Z]+|(#\d+));)/) { |special| ERB::Util::HTML_ESCAPE[special] }
107:       end

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" />

[Source]

    # File vendor/rails/actionpack/lib/action_view/helpers/tag_helper.rb, line 40
40:       def tag(name, options = nil, open = false, escape = true)
41:         "<#{name}#{tag_options(options, escape) if options}#{open ? ">" : " />"}".html_safe
42:       end

[Validate]