Module: ActionView::Helpers::TagHelper

Relationships & Source Files
Extension / Inclusion / Inheritance Descendants
Included In: ::ActionView::Base, ::ActionView::Helpers, AssetTagHelper, ActionView::Helpers::DateTimeSelector, DebugHelper, FormHelper, FormOptionsHelper, FormTagHelper, ActionView::Helpers::Tags::Base, ActionView::Helpers::Tags::CheckBox, ActionView::Helpers::Tags::CollectionCheckBoxes, ActionView::Helpers::Tags::CollectionRadioButtons, ActionView::Helpers::Tags::CollectionSelect, ActionView::Helpers::Tags::ColorField, ActionView::Helpers::Tags::DateField, ActionView::Helpers::Tags::DateSelect, ActionView::Helpers::Tags::DatetimeField, ActionView::Helpers::Tags::DatetimeLocalField, ActionView::Helpers::Tags::DatetimeSelect, ActionView::Helpers::Tags::EmailField, ActionView::Helpers::Tags::FileField, ActionView::Helpers::Tags::GroupedCollectionSelect, ActionView::Helpers::Tags::HiddenField, ActionView::Helpers::Tags::Label, ActionView::Helpers::Tags::MonthField, ActionView::Helpers::Tags::NumberField, ActionView::Helpers::Tags::PasswordField, ActionView::Helpers::Tags::RadioButton, ActionView::Helpers::Tags::RangeField, ActionView::Helpers::Tags::SearchField, ActionView::Helpers::Tags::Select, ActionView::Helpers::Tags::TelField, ActionView::Helpers::Tags::TextArea, ActionView::Helpers::Tags::TextField, ActionView::Helpers::Tags::TimeField, ActionView::Helpers::Tags::TimeSelect, ActionView::Helpers::Tags::TimeZoneSelect, ActionView::Helpers::Tags::UrlField, ActionView::Helpers::Tags::WeekField, TextHelper, TranslationHelper, UrlHelper, ::ActionView::TestCase, ::ActionView::TestCase::Behavior
Super Chains via Extension / Inclusion / Inheritance
Class Chain: self, ::ActiveSupport::Concern
Instance Chain: self, CaptureHelper
Defined in:	actionview/lib/action_view/helpers/tag_helper.rb

Overview

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

Constant Summary

BOOLEAN_ATTRIBUTES =
# File 'actionview/lib/action_view/helpers/tag_helper.rb', line 14

%w(disabled readonly multiple checked autobuffer
autoplay controls loop selected hidden scoped async
defer reversed ismap seamless muted required
autofocus novalidate formnovalidate open pubdate
itemscope allowfullscreen default inert sortable
truespeed typemustmatch).to_set

PRE_CONTENT_STRINGS =
# File 'actionview/lib/action_view/helpers/tag_helper.rb', line 25
```
{
  :textarea => "\n"
}
```
TAG_PREFIXES =
# File 'actionview/lib/action_view/helpers/tag_helper.rb', line 23
```
['aria', 'data', :aria, :data].to_set
```

Class Method Summary

::ActiveSupport::Concern - Extended

append_features, class_methods, included

Instance Method Summary

#cdata_section(content)

Returns a CDATA section with the given content.
#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.
#escape_once(html)

Returns an escaped version of html without affecting existing escaped entities.
#tag(name, options = nil, open = false, escape = true)

Returns an empty HTML tag of type name which by default is XHTML compliant.

CaptureHelper - Included

#capture	The capture method allows you to extract part of a template into a variable.
#content_for	Calling content_for stores a block of markup in an identifier for later use.
#content_for?	content_for? checks whether any content has been captured yet using `content_for`.
#provide	The same as `content_for` but when used with streaming flushes straight back to the layout.

Instance Method Details

#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 ]]>.

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

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

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

[ GitHub ]

# File 'actionview/lib/action_view/helpers/tag_helper.rb', line 125


def cdata_section(content)
  splitted = content.to_s.gsub(/\]\]\>/, ']]]]><![CDATA[>')
  "<![CDATA[#{splitted}]]>".html_safe
end

#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 can be 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(:div, "Hello world!", class: ["strong", "highlight"])
 # => <div class="strong highlight">Hello world!</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>

[ GitHub ]

# File 'actionview/lib/action_view/helpers/tag_helper.rb', line 103


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_string(name, capture(&block), options, escape)
  else
    content_tag_string(name, content_or_options_with_block, options, escape)
  end
end

#escape_once(html)

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

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

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

[ GitHub ]

# File 'actionview/lib/action_view/helpers/tag_helper.rb', line 137


def escape_once(html)
  ERB::Util.html_escape_once(html)
end

#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

You can use symbols or strings for the attribute names.

Use true with boolean attributes that can render with no value, like disabled and readonly.

HTML5 data-* attributes can be set with a single data key pointing to a hash of sub-attributes.

To play nicely with JavaScript conventions sub-attributes are dasherized. For example, a key user_id would render as data-user-id and thus accessed as dataset.userId.

Values are encoded to JSON, with the exception of strings, symbols and BigDecimals. This may come in handy when using jQuery's HTML5-aware .data() from 1.4.3.

Examples

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

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

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

tag("input", type: 'text', class: ["strong", "highlight"])
# => <input class="strong highlight" type="text" />

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" />

tag("div", data: {name: 'Stephen', city_state: %w(Chicago IL)})
# => <div data-name="Stephen" data-city-state="[&quot;Chicago&quot;,&quot;IL&quot;]" />

[ GitHub ]

# File 'actionview/lib/action_view/helpers/tag_helper.rb', line 74


def tag(name, options = nil, open = false, escape = true)
  "<#{name}#{tag_options(options, escape) if options}#{open ? ">" : " />"}".html_safe
end