Defines an Element Attribute; IE, a attribute=value pair, as in: <element attribute=“value”/>. Attributes can be in their own namespaces. General users of REXML will not interact with the Attribute class much.
Constructor. FIXME: The parser doesn't catch illegal characters in attributes
Either: an Attribute, which this new attribute will become a clone of; or a String, which is the name of this attribute
If first
is an Attribute, then
this may be an Element, or nil. If nil, then the
Element parent of this attribute is the parent
of the first
Attribute. If the
first argument is a String, then this must also be a String, and is the
content of the attribute.
If this is the content, it must be fully normalized (contain no illegal characters).
Ignored unless first
is a String; otherwise, may be the Element parent of this attribute, or nil.
Attribute.new( attribute_to_clone ) Attribute.new( attribute_to_clone, parent_element ) Attribute.new( "attr", "attr_value" ) Attribute.new( "attr", "attr_value", parent_element )
# File rexml/attribute.rb, line 42 def initialize( first, second=nil, parent=nil ) @normalized = @unnormalized = @element = nil if first.kind_of? Attribute self.name = first.expanded_name @unnormalized = first.value if second.kind_of? Element @element = second else @element = first.element end elsif first.kind_of? String @element = parent self.name = first @normalized = second.to_s else raise "illegal argument #{first.class.name} to Attribute constructor" end end
Returns true if other is an Attribute and has the same name and value, false otherwise.
# File rexml/attribute.rb, line 90 def ==( other ) other.kind_of?(Attribute) and other.name==name and other.value==value end
Returns a copy of this attribute
# File rexml/attribute.rb, line 143 def clone Attribute.new self end
Sets the element of which this object is an attribute. Normally, this is not directly called.
Returns this attribute
# File rexml/attribute.rb, line 151 def element=( element ) @element = element self end
Creates (and returns) a hash from both the name and value
# File rexml/attribute.rb, line 95 def hash name.hash + value.hash end
# File rexml/attribute.rb, line 172 def inspect rv = "" write( rv ) rv end
Returns the namespace URL, if defined, or nil otherwise
e = Element.new("el") e.add_attributes({"xmlns:ns", "http://url"}) e.namespace( "ns" ) # -> "http://url"
# File rexml/attribute.rb, line 83 def namespace arg=nil arg = prefix if arg.nil? @element.namespace arg end
Returns the namespace of the attribute.
e = Element.new( "elns:myelement" ) e.add_attribute( "nsa:a", "aval" ) e.add_attribute( "b", "bval" ) e.attributes.get_attribute( "a" ).prefix # -> "nsa" e.attributes.get_attribute( "b" ).prefix # -> "elns" a = Attribute.new( "x", "y" ) a.prefix # -> ""
# File rexml/attribute.rb, line 70 def prefix pf = super if pf == "" pf = @element.prefix if @element end pf end
Removes this Attribute from the tree, and returns true if successfull
This method is usually not called directly.
# File rexml/attribute.rb, line 159 def remove @element.attributes.delete self.name unless @element.nil? end
Returns the attribute value, with entities replaced
# File rexml/attribute.rb, line 114 def to_s return @normalized if @normalized doctype = nil if @element doc = @element.document doctype = doc.doctype if doc end @normalized = Text::normalize( @unnormalized, doctype ) @unnormalized = nil @normalized end
Returns this attribute out as XML source, expanding the name
a = Attribute.new( "x", "y" ) a.to_string # -> "x='y'" b = Attribute.new( "ns:x", "y" ) b.to_string # -> "ns:x='y'"
# File rexml/attribute.rb, line 105 def to_string if @element and @element.context and @element.context[:attribute_quote] == :quote %Q^#@expanded_name="#{to_s().gsub(/"/, '"e;')}"^ else "#@expanded_name='#{to_s().gsub(/'/, ''')}'" end end
Returns the UNNORMALIZED value of this attribute. That is, entities have been expanded to their values
# File rexml/attribute.rb, line 130 def value return @unnormalized if @unnormalized doctype = nil if @element doc = @element.document doctype = doc.doctype if doc end @unnormalized = Text::unnormalize( @normalized, doctype ) @normalized = nil @unnormalized end