Provides methods to generate HTML tags programmatically when you can‘t use a Builder. By default, they output XHTML compliant tags.
| BOOLEAN_ATTRIBUTES | = | %w(disabled readonly multiple checked).to_set |
| BLOCK_CALLED_FROM_ERB | = | 'defined? __in_erb_template' |
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]]>
[ show source ]
# File actionpack/lib/action_view/helpers/tag_helper.rb, line 94
94: def cdata_section(content)
95: "<![CDATA[#{content}]]>".html_safe
96: 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>
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# File actionpack/lib/action_view/helpers/tag_helper.rb, line 68
68: def content_tag(name, content_or_options_with_block = nil, options = nil, escape = true, &block)
69: if block_given?
70: options = content_or_options_with_block if content_or_options_with_block.is_a?(Hash)
71: content_tag = content_tag_string(name, capture(&block), options, escape)
72:
73: if block_called_from_erb?(block)
74: concat(content_tag)
75: else
76: content_tag
77: end
78: else
79: content_tag_string(name, content_or_options_with_block, options, escape)
80: end
81: end
Returns an escaped version of html without affecting existing escaped entities.
Examples
escape_once("1 < 2 & 3")
# => "1 < 2 & 3"
escape_once("<< Accept & Checkout")
# => "<< Accept & Checkout"
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# File actionpack/lib/action_view/helpers/tag_helper.rb, line 106
106: def escape_once(html)
107: ActiveSupport::Multibyte.clean(html.to_s).gsub(/[\"><]|&(?!([a-zA-Z]+|(#\d+));)/) { |special| ERB::Util::HTML_ESCAPE[special] }
108: 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 & shut.png" />
tag("img", { :src => "open & shut.png" }, false, false)
# => <img src="open & shut.png" />
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# File actionpack/lib/action_view/helpers/tag_helper.rb, line 41
41: def tag(name, options = nil, open = false, escape = true)
42: "<#{name}#{tag_options(options, escape) if options}#{open ? ">" : " />"}".html_safe
43: end