Provides methods to generate HTML tags programmatically when you can't use a Builder. By default, they output XHTML compliant tags.

Methods
C
E
T
Included Modules
Constants
BOOLEAN_ATTRIBUTES = %w(disabled readonly multiple checked).to_set
 
BLOCK_CALLED_FROM_ERB = 'defined? __in_erb_template'
 
Instance Public methods
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]]>
# File actionpack/lib/action_view/helpers/tag_helper.rb, line 94
def cdata_section(content)
  "<![CDATA[#{content}]]>".html_safe
end
content_tag(name, content_or_options_with_block = nil, options = nil, escape = true, &block)

Returns an HTML block tag of type namesurrounding 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 optionsas the second parameter. Set escape to false to disable attribute value escaping.

Options

The optionshash is used with attributes with no value like ( disabledand readonly), which you can give a value of true in the optionshash. 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>
# File actionpack/lib/action_view/helpers/tag_helper.rb, line 68
def content_tag(name, content_or_options_with_block = nil, options = nil, escape = true, &block)
  if block_given?
    options = content_or_options_with_block if content_or_options_with_block.is_a?(Hash)
    content_tag = content_tag_string(name, capture(&block), options, escape)
    if block_called_from_erb?(block)
      concat(content_tag)
    else
      content_tag
    end
  else
    content_tag_string(name, content_or_options_with_block, options, escape)
  end
end
escape_once(html)

Returns an escaped version of htmlwithout 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"
# File actionpack/lib/action_view/helpers/tag_helper.rb, line 106
def escape_once(html)
  ActiveSupport::Multibyte.clean(html.to_s).gsub(/[\"><]|&(?!([a-zA-Z]+|(#\d+));)/) { |special| ERB::Util::HTML_ESCAPE[special] }
end
tag(name, options = nil, open = false, escape = true)

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

Options

The optionshash is used with attributes with no value like ( disabledand readonly), which you can give a value of true in the optionshash. 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" />
# File actionpack/lib/action_view/helpers/tag_helper.rb, line 41
def tag(name, options = nil, open = false, escape = true)
  "<#{name}#{tag_options(options, escape) if options}#{open ? ">" : " />"}".html_safe
end