Class | Builder::XmlMarkup |
In: |
vendor/rails/activesupport/lib/active_support/vendor/builder/xmlmarkup.rb
|
Parent: | XmlBase |
Create XML markup easily. All (well, almost all) methods sent to an XmlMarkup object will be translated to the equivalent XML markup. Any method with a block will be treated as an XML markup tag with nested markup in the block.
Examples will demonstrate this easier than words. In the following, xm is an XmlMarkup object.
xm.em("emphasized") # => <em>emphasized</em> xm.em { xmm.b("emp & bold") } # => <em><b>emph & bold</b></em> xm.a("A Link", "href"=>"http://onestepback.org") # => <a href="http://onestepback.org">A Link</a> xm.div { br } # => <div><br/></div> xm.target("name"=>"compile", "option"=>"fast") # => <target option="fast" name="compile"\> # NOTE: order of attributes is not specified. xm.instruct! # <?xml version="1.0" encoding="UTF-8"?> xm.html { # <html> xm.head { # <head> xm.title("History") # <title>History</title> } # </head> xm.body { # <body> xm.comment! "HI" # <!-- HI --> xm.h1("Header") # <h1>Header</h1> xm.p("paragraph") # <p>paragraph</p> } # </body> } # </html>
Example:
xm.div { # <div> xm.text! "line"; xm.br # line<br/> xm.text! "another line"; xmbr # another line<br/> } # </div>
Example:
xml.tag!("SOAP:Envelope") { ... }
will produce …
<SOAP:Envelope> ... </SOAP:Envelope>"
tag! will also take text and attribute arguments (after the tag name) like normal markup methods. (But see the next bullet item for a better way to handle XML namespaces).
xml.SOAP :Envelope do ... end
Just put a space before the colon in a namespace to produce the right form for builder (e.g. "SOAP:Envelope" => "xml.SOAP :Envelope")
Examples:
xm = Builder::XmlMarkup.new result = xm.title("yada") # result is a string containing the markup. buffer = "" xm = Builder::XmlMarkup.new(buffer) # The markup is appended to buffer (using <<) xm = Builder::XmlMarkup.new(STDOUT) # The markup is written to STDOUT (using <<) xm = Builder::XmlMarkup.new x2 = Builder::XmlMarkup.new(:target=>xm) # Markup written to +x2+ will be send to +xm+.
Example:
xm = Builder.new(:ident=>2) # xm will produce nicely formatted and indented XML. xm = Builder.new(:indent=>2, :margin=>4) # xm will produce nicely formatted and indented XML with 2 # spaces per indent and an over all indentation level of 4. builder = Builder::XmlMarkup.new(:target=>$stdout, :indent=>2) builder.name { |b| b.first("Jim"); b.last("Weirich) } # prints: # <name> # <first>Jim</first> # <last>Weirich</last> # </name>
xml.div { strong("text") }
you need to write:
xml.div { xml.strong("text") }
Although more verbose, the subtle change in semantics within the block was found to be prone to error. To make this change a little less cumbersome, the markup block now gets the markup object sent as an argument, allowing you to use a shorter alias within the block.
For example:
xml_builder = Builder::XmlMarkup.new xml_builder.div { |xml| xml.stong("text") }
Create an XML markup builder. Parameters are specified by an option hash.
:target=>target_object: | Object receiving the markup. out must respond to the << operator. The default is a plain string target. |
:indent=>indentation: | Number of spaces used for indentation. The default is no indentation and no line breaks. |
:margin=>initial_indentation_level: | Amount of initial indentation (specified in levels, not spaces). |
# File vendor/rails/activesupport/lib/active_support/vendor/builder/xmlmarkup.rb, line 175 175: def initialize(options={}) 176: indent = options[:indent] || 0 177: margin = options[:margin] || 0 178: super(indent, margin) 179: @target = options[:target] || "" 180: end
Surrounds the given text with a CDATA tag
For example:
xml.cdata! "blah blah blah" # => <![CDATA[blah blah blah]]>
# File vendor/rails/activesupport/lib/active_support/vendor/builder/xmlmarkup.rb, line 248 248: def cdata!(text) 249: _ensure_no_block block_given? 250: _special("<![CDATA[", "]]>", text, nil) 251: end
# File vendor/rails/activesupport/lib/active_support/vendor/builder/xmlmarkup.rb, line 187 187: def comment!(comment_text) 188: _ensure_no_block block_given? 189: _special("<!-- ", " -->", comment_text, nil) 190: end
Insert an XML declaration into the XML markup.
For example:
xml.declare! :ELEMENT, :blah, "yada" # => <!ELEMENT blah "yada">
# File vendor/rails/activesupport/lib/active_support/vendor/builder/xmlmarkup.rb, line 198 198: def declare!(inst, *args, &block) 199: _indent 200: @target << "<!#{inst}" 201: args.each do |arg| 202: case arg 203: when String 204: @target << %{ "#{arg}"} 205: when Symbol 206: @target << " #{arg}" 207: end 208: end 209: if block_given? 210: @target << " [" 211: _newline 212: _nested_structures(block) 213: @target << "]" 214: end 215: @target << ">" 216: _newline 217: end
Insert a processing instruction into the XML markup. E.g.
For example:
xml.instruct! #=> <?xml version="1.0" encoding="UTF-8"?> xml.instruct! :aaa, :bbb=>"ccc" #=> <?aaa bbb="ccc"?>
# File vendor/rails/activesupport/lib/active_support/vendor/builder/xmlmarkup.rb, line 228 228: def instruct!(directive_tag=:xml, attrs={}) 229: _ensure_no_block block_given? 230: if directive_tag == :xml 231: a = { :version=>"1.0", :encoding=>"UTF-8" } 232: attrs = a.merge attrs 233: end 234: _special( 235: "<?#{directive_tag}", 236: "?>", 237: nil, 238: attrs, 239: [:version, :encoding, :standalone]) 240: end