REXML::Element

Constructor

• :respect_whitespace the value of this is :all or an array of strings being the names of the elements to respect whitespace for. Defaults to :all.
• :compress_whitespace the value can be :all or an array of strings being the names of the elements to ignore whitespace on. Overrides :respect_whitespace.
• :ignore_whitespace_nodes the value can be :all or an array of strings being the names of the elements in which to ignore whitespace-only nodes. If this is set, Text nodes which contain only whitespace will not be added to the document tree.
• :raw can be :all, or an array of strings being the names of the elements to process in raw mode. In raw mode, special characters in text is not converted to or from entities.

Adds an attribute to this element, overwriting any existing attribute by the same name.

 e = Element.new 'e'
 e.add_attribute( 'a', 'b' )               #-> <e a='b'/>
 e.add_attribute( 'x:a', 'c' )             #-> <e a='b' x:a='c'/>
 e.add_attribute Attribute.new('b', 'd')   #-> <e a='b' x:a='c' b='d'/>

Add multiple attributes to this element.

 el.add_attributes( {"name1"=>"value1", "name2"=>"value2"} )
 el.add_attributes( [ ["name1","value1"], ["name2"=>"value2"] ] )

Adds a child to this element, optionally setting attributes in the element.

 el = doc.add_element 'my-tag'
 el = doc.add_element 'my-tag', {'attr1'=>'val1', 'attr2'=>'val2'}
 el = Element.new 'my-tag'
 doc.add_element el

Adds a namespace to this element.

Evaluates to: this Element

 a = Element.new("a")
 a.add_namespace("xmlns:foo", "bar" )
 a.add_namespace("foo", "bar")  # shorthand for previous line
 a.add_namespace("twiddle")
 puts a   #-> <a xmlns:foo='bar' xmlns='twiddle'/>

A helper method to add a Text child. Actual Text instances can be added with regular Parent methods, such as add() and <<()

 e = Element.new('a')          #-> <e/>
 e.add_text 'foo'              #-> <e>foo</e>
 e.add_text Text.new(' bar')    #-> <e>foo bar</e>

Note that at the end of this example, the branch has 3 nodes; the ‘e’ element and 2 Text node children.

Attributes #

Get an array of all CData children. IMMUTABLE

Creates a shallow copy of self.

  d = Document.new "<a><b/><b/><c><d/></c></a>"
  new_a = d.root.clone
  puts new_a  # => "<a/>"

Get an array of all Comment children. IMMUTABLE

Removes an attribute

 e = Element.new('E')
 e.add_attribute( 'name', 'Sean' )             #-> <E name='Sean'/>
 r = e.add_attribute( 'sur:name', 'Russell' )  #-> <E name='Sean' sur:name='Russell'/>
 e.delete_attribute( 'name' )                  #-> <E sur:name='Russell'/>
 e.delete_attribute( r )                       #-> <E/>

Deletes a child element.

 doc.delete_element "/a/b/c[@id='4']"
 doc.delete_element doc.elements["//k"]
 doc.delete_element 1

Removes a namespace from this node. This only works if the namespace is actually declared in this node. If no argument is passed, deletes the default namespace.

Evaluates to: this element

 doc = Document.new "<a xmlns:foo='bar' xmlns='twiddle'/>"
 doc.root.delete_namespace
 puts doc     # -> <a xmlns:foo='bar'/>
 doc.root.delete_namespace 'foo'
 puts doc     # -> <a/>

Evaluates to the document to which this element belongs, or nil if this element doesn‘t belong to a document.

Synonym for Element.elements.each

Iterates through the child elements, yielding for each Element that has a particular attribute set.

 doc = Document.new "<a><b @id='1'/><c @id='2'/><d @id='1'/><e/></a>"
 # Yields b, c, d
 doc.root.each_element_with_attribute( 'id' ) {|e| p e}
 # Yields b, d
 doc.root.each_element_with_attribute( 'id', '1' ) {|e| p e}
 # Yields b
 doc.root.each_element_with_attribute( 'id', '1', 1 ) {|e| p e}
 # Yields d
 doc.root.each_element_with_attribute( 'id', '1', 0, 'd' ) {|e| p e}

Iterates through the children, yielding for each Element that has a particular text set.

 doc = Document.new '<a><b>b</b><c>b</c><d>d</d><e/></a>'
 # Yields b, c, d
 doc.each_element_with_text {|e|p e}
 # Yields b, c
 doc.each_element_with_text('b'){|e|p e}
 # Yields b
 doc.each_element_with_text('b', 1){|e|p e}
 # Yields d
 doc.each_element_with_text(nil, 0, 'd'){|e|p e}

Synonym for Element.to_a This is a little slower than calling elements.each directly.

Returns the first child Text node, if any, or nil otherwise. This method returns the actual Text node, rather than the String content.

 doc = Document.new "<p>some text <b>this is bold!</b> more text</p>"
 # The element 'p' has two text elements, "some text " and " more text".
 doc.root.get_text.value            #-> "some text "

Evaluates to true if this element has any attributes set, false otherwise.

Evaluates to true if this element has at least one child Element

 doc = Document.new "<a><b/><c>Text</c></a>"
 doc.root.has_elements               # -> true
 doc.elements["/a/b"].has_elements   # -> false
 doc.elements["/a/c"].has_elements   # -> false

Evaluates to true if this element has at least one Text child

Get an array of all Instruction children. IMMUTABLE

Evalutas to the URI for a prefix, or the empty string if no such namespace is declared for this element. Evaluates recursively for ancestors. Returns the default namespace, if there is one.

 doc = Document.new("<a xmlns='1' xmlns:y='2'><b/><c xmlns:z='3'/></a>")
 b = doc.elements['//b']
 b.namespace           # -> '1'
 b.namespace("y")      # -> '2'

Returns the next sibling that is an element, or nil if there is no Element sibling after this one

 doc = Document.new '<a><b/>text<c/></a>'
 doc.root.elements['b'].next_element          #-> <c/>
 doc.root.elements['c'].next_element          #-> nil

Evaluates to an Array containing the prefixes (names) of all defined namespaces at this context node.

 doc = Document.new("<a xmlns:x='1' xmlns:y='2'><b/><c xmlns:z='3'/></a>")
 doc.elements['//b'].prefixes # -> ['x', 'y']

Returns the previous sibling that is an element, or nil if there is no Element sibling prior to this one

 doc = Document.new '<a><b/>text<c/></a>'
 doc.root.elements['c'].previous_element          #-> <b/>
 doc.root.elements['b'].previous_element          #-> nil

Evaluates to true if raw mode is set for this element. This is the case if the context has :raw set to :all or an array containing the name of this element.

The evaluation is tested against expanded_name, and so is namespace sensitive.

Evaluates to the root node of the document that this element belongs to. If this element doesn‘t belong to a document, but does belong to another Element, the parent‘s root will be returned, until the earliest ancestor is found.

Note that this is not the same as the document element. In the following example, <a> is the document element, and the root node is the parent node of the document element. You may ask yourself why the root node is useful: consider the doctype and XML declaration, and any processing instructions before the document element… they are children of the root node, or siblings of the document element. The only time this isn‘t true is when an Element is created that is not part of any Document. In this case, the ancestor that has no parent acts as the root node.

 d = Document.new '<a><b><c/></b></a>'
 a = d[1] ; c = a[1][1]
 d.root_node == d   # TRUE
 a.root_node        # namely, d
 c.root_node        # again, d

A convenience method which returns the String value of the first child text element, if one exists, and nil otherwise.

Note that an element may have multiple Text elements, perhaps separated by other children. Be aware that this method only returns the first Text node.

This method returns the value of the first text child node, which ignores the raw setting, so always returns normalized text. See the Text::value documentation.

 doc = Document.new "<p>some text <b>this is bold!</b> more text</p>"
 # The element 'p' has two text elements, "some text " and " more text".
 doc.root.text              #-> "some text "

Sets the first Text child of this object. See text() for a discussion about Text children.

If a Text child already exists, the child is replaced by this content. This means that Text content can be deleted by calling this method with a nil argument. In this case, the next Text child becomes the first Text child. In no case is the order of any siblings disturbed.

 doc = Document.new '<a><b/></a>'
 doc.root.text = 'Sean'      #-> '<a><b/>Sean</a>'
 doc.root.text = 'Elliott'   #-> '<a><b/>Elliott</a>'
 doc.root.add_element 'c'    #-> '<a><b/>Elliott<c/></a>'
 doc.root.text = 'Russell'   #-> '<a><b/>Russell<c/></a>'
 doc.root.text = nil         #-> '<a><b/><c/></a>'

Get an array of all Text children. IMMUTABLE

Evaluates to true if whitespace is respected for this element. This is the case if:

1. Neither :respect_whitespace nor :compress_whitespace has any value
2. The context has :respect_whitespace set to :all or an array containing the name of this element, and :compress_whitespace isn‘t set to :all or an array containing the name of this element.

The evaluation is tested against expanded_name, and so is namespace sensitive.

DEPRECATED

See REXML::Formatters

Writes out this element, and recursively, all children.

  document will be written.

 out = ''
 doc.write( out )     #-> doc is written to the string 'out'
 doc.write( $stdout ) #-> doc written to the console