Module: ActionView::Helpers::TagHelper

Includes:
ERB::Util
Included in:
DateHelper, InstanceTag
Defined in:
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 collapse

BOOLEAN_ATTRIBUTES = 
%w(disabled readonly multiple).to_set

Constants included from ERB::Util

ERB::Util::HTML_ESCAPE, ERB::Util::JSON_ESCAPE

Instance Method Summary collapse

Methods included from ERB::Util

#html_escape, j, json_escape

Instance Method Details

#cdata_section(content) ⇒ Object

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]]>



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# File 'lib/action_view/helpers/tag_helper.rb', line 91

def cdata_section(content)
  "<![CDATA[#{content}]]>"
end

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

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"><p>Hello world!</p></div>



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# File '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 = capture(&block)
    content_tag = content_tag_string(name, content, options, escape)
    block_is_within_action_view?(block) ? concat(content_tag, block.binding) : content_tag
  else
    content = content_or_options_with_block
    content_tag_string(name, content, options, escape)
  end
end

#escape_once(html) ⇒ Object

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"



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

def escape_once(html)
  html.to_s.gsub(/[\"><]|&(?!([a-zA-Z]+|(#\d+));)/) { |special| ERB::Util::HTML_ESCAPE[special] }
end

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

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" />



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# File '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 ? ">" : " />"}"
end