# struct XML::Node

- XML::Node
- Struct
- Value
- Object

##
Defined in:

##
Constant Summary

LOOKS_LIKE_XPATH = `/^(\.\/|\/|\.\.|\.$)/`

##
Constructors

- .new(node : Pointer(LibXML::Attr))

  Creates a new node.

- .new(node : Pointer(LibXML::Doc))

  Creates a new node.

- .new(node : Pointer(LibXML::Node))

  Creates a new node.

##
Instance Method Summary

- #==(other : Node)

  Compares with other.

- #[](attribute : String) : String

  Gets the attribute content for the attribute given by name.

- #[]=(name : String, value)

  Sets attribute of this node to value.

- #[]?(attribute : String) : String?

  Gets the attribute content for the attribute given by name.

- #attribute?

  Returns `true` if this is an attribute node.

- #attributes

  Returns attributes of this node as an `XML::Attributes`.

- #cdata?

  Returns `true` if this is a `CDATA` section node.

- #children

  Gets the list of children for this node as a `XML::NodeSet`.

- #comment?

  Returns `true` if this is a comment node.

- #content : String

  Returns the content for this Node.

- #content=(content)

  Sets the Node's content to a Text node containing string.

- #delete(name : String)

  Deletes attribute given by name.

- #document

  Gets the document for this Node as a `XML::Node`.

- #document?

  Returns `true` if this is a Document or HTML Document node.

- #element?

  Returns `true` if this is an Element node.

- #encoding

  Returns the encoding of this node's document.

- #errors

  Returns the list of `XML::Error` found when parsing this document.

- #first_element_child

  Returns the first child node of this node that is an element.

- #fragment?

  Returns `true` if this is a DocumentFragment.

- #hash(hasher)

  See `Object#hash(hasher)`

- #inner_text

  Returns the content for this Node.

- #inspect(io : IO) : Nil

  Returns detailed information for this node including node type, name, attributes and children.

- #name

  Returns the name for this Node.

- #name=(name)

  Sets the name for this Node.

- #namespace

  Returns the namespace for this node or `nil` if not found.

- #namespace_scopes

  Returns namespaces in scope for self – those defined on self element directly or any ancestor node – as an `Array` of `XML::Namespace` objects.

- #namespaces

  Returns a `Hash(String, String?) of prefix => href` for all namespaces on this node and its ancestors.

- #next

  Returns the next sibling node or `nil` if not found.

- #next_element

  Returns the next element node sibling or `nil` if not found.

- #next_sibling

  Returns the next sibling node or `nil` if not found.

- #object_id

  Returns the address of underlying `LibXML::Node*` in memory.

- #parent

  Returns the parent node or `nil` if not found.

- #previous

  Returns the previous sibling node or `nil` if not found.

- #previous_element

  Returns the previous sibling node that is an element or `nil` if not found.

- #previous_sibling

  Returns the previous sibling node or `nil` if not found.

- #processing_instruction?

  Returns `true` if this is a Processing Instruction node.

- #root

  Returns the root node for this document or `nil`.

- #text

  Same as `#content`.

- #text=(text)

  Same as `#content=`.

- #text?

  Returns `true` if this is a Text node.

- #to_s(io : IO) : Nil

  Serialize this Node as XML to io using default options.

- #to_unsafe : Pointer(LibXML::Node)

  Returns underlying `LibXML::Node*` instance.

- #to_xml(indent : Int = 2, indent_text = " ", options : SaveOptions = SaveOptions.xml_default)

  Serialize this Node as XML and return a `String` using default options.

- #to_xml(io : IO, indent = 2, indent_text = " ", options : SaveOptions = SaveOptions.xml_default)

  Serialize this Node as XML to io using default options.

- #type

  Returns the type for this Node as `XML::Node::Type`.

- #unlink

  Removes the node from the XML document.

- #version

  Returns the version of this node's document.

- #xml?

  Returns `true` if this is an xml Document node.

- #xpath(path, namespaces = nil, variables = nil)

  Searches this node for XPath path.

- #xpath_bool(path, namespaces = nil, variables = nil)

  Searches this node for XPath path and restricts the return type to `Bool`.

- #xpath_float(path, namespaces = nil, variables = nil)

  Searches this node for XPath path and restricts the return type to `Float64`.

- #xpath_node(path, namespaces = nil, variables = nil)

  Searches this node for XPath path for nodes and returns the first one.

- #xpath_nodes(path, namespaces = nil, variables = nil)

  Searches this node for XPath path and restricts the return type to `NodeSet`.

- #xpath_string(path, namespaces = nil, variables = nil)

  Searches this node for XPath path and restricts the return type to `String`.

### Instance methods inherited from struct `Struct`

==(other) : Bool ==, hash(hasher) hash, inspect(io : IO) : Nil inspect, pretty_print(pp) : Nil pretty_print, to_s(io : IO) : Nil to_s

### Instance methods inherited from struct `Value`

==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup

### Instance methods inherited from class `Object`

!=(other) !=, !~(other) !~, ==(other) ==, ===(other : JSON::Any)
===(other : YAML::Any)
===(other) ===, =~(other) =~, __crystal_pseudo_! : Bool __crystal_pseudo_!, __crystal_pseudo_as(type : Class) __crystal_pseudo_as, __crystal_pseudo_as?(type : Class) __crystal_pseudo_as?, __crystal_pseudo_is_a?(type : Class) : Bool __crystal_pseudo_is_a?, __crystal_pseudo_nil? : Bool __crystal_pseudo_nil?, __crystal_pseudo_responds_to?(name : Symbol) : Bool __crystal_pseudo_responds_to?, class class, dup dup, hash(hasher)
hash hash, inspect : String
inspect(io : IO) : Nil inspect, itself itself, not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, tap(&) tap, to_json(io : IO)
to_json to_json, to_pretty_json(indent : String = " ")
to_pretty_json(io : IO, indent : String = " ") to_pretty_json, to_s : String
to_s(io : IO) : Nil to_s, to_yaml(io : IO)
to_yaml to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as

### Class methods inherited from class `Object`

from_json(string_or_io, root : String)
from_json(string_or_io) from_json, from_yaml(string_or_io : String | IO) from_yaml

##
Constructor Detail

def self.new(node : Pointer(LibXML::Attr)) #

Creates a new node.

def self.new(node : Pointer(LibXML::Doc)) #

Creates a new node.

def self.new(node : Pointer(LibXML::Node)) #

Creates a new node.

##
Instance Method Detail

def ==(other : Node) #

Compares with other.

def [](attribute : String) : String #

Gets the attribute content for the attribute given by name. Raises `KeyError` if attribute is not found.

def []=(name : String, value) #

Sets attribute of this node to value. Raises `XML::Error` if this node does not support attributes.

def []?(attribute : String) : String? #

Gets the attribute content for the attribute given by name. Returns `nil` if attribute is not found.

def attribute? #

Returns `true` if this is an attribute node.

def attributes #

Returns attributes of this node as an `XML::Attributes`.

def cdata? #

Returns `true` if this is a `CDATA` section node.

def children #

Gets the list of children for this node as a `XML::NodeSet`.

def comment? #

Returns `true` if this is a comment node.

def content : String #

Returns the content for this Node. An empty string is returned if the node has no content.

def content=(content) #

Sets the Node's content to a Text node containing string. The string gets XML escaped, not interpreted as markup.

def delete(name : String) #

Deletes attribute given by name. Returns attributes value, or `nil` if attribute not found.

def document #

Gets the document for this Node as a `XML::Node`.

def document? #

Returns `true` if this is a Document or HTML Document node.

def element? #

Returns `true` if this is an Element node.

def encoding #

Returns the encoding of this node's document.

def errors #

Returns the list of `XML::Error` found when parsing this document. Returns `nil` if no errors were found.

def first_element_child #

Returns the first child node of this node that is an element. Returns `nil` if not found.

def fragment? #

Returns `true` if this is a DocumentFragment.

def hash(hasher) #

See `Object#hash(hasher)`

def inner_text #

Returns the content for this Node.

def inspect(io : IO) : Nil #

Returns detailed information for this node including node type, name, attributes and children.

def name #

Returns the name for this Node.

def name=(name) #

Sets the name for this Node.

def namespace #

Returns the namespace for this node or `nil` if not found.

def namespace_scopes #

Returns namespaces in scope for self – those defined on self element directly or any ancestor node – as an `Array` of `XML::Namespace` objects.

Default namespaces (`"xmlns="` style) for self are included in this array; Default namespaces for ancestors, however, are not.

See also `#namespaces`

def namespaces #

Returns a `Hash(String, String?) of prefix => href` for all namespaces on this node and its ancestors.

This method returns the same namespaces as `#namespace_scopes`.

Returns namespaces in scope for self – those defined on self element directly or any ancestor node – as a `Hash` of attribute-name/value pairs.

NOTE Note that the keys in this hash XML attributes that would be used to define this namespace, such as `"xmlns:prefix"`, not just the prefix.

def next #

Returns the next sibling node or `nil` if not found.

def next_element #

Returns the next element node sibling or `nil` if not found.

def next_sibling #

Returns the next sibling node or `nil` if not found.

def object_id #

Returns the address of underlying `LibXML::Node*` in memory.

def parent #

Returns the parent node or `nil` if not found.

def previous #

Returns the previous sibling node or `nil` if not found.

def previous_element #

Returns the previous sibling node that is an element or `nil` if not found.

def previous_sibling #

Returns the previous sibling node or `nil` if not found. Same with `#previous`.

def processing_instruction? #

Returns `true` if this is a Processing Instruction node.

def root #

Returns the root node for this document or `nil`.

def text #

Same as `#content`.

def text=(text) #

Same as `#content=`.

def text? #

Returns `true` if this is a Text node.

def to_s(io : IO) : Nil #

Serialize this Node as XML to io using default options.

See `#to_xml`.

def to_unsafe : Pointer(LibXML::Node) #

Returns underlying `LibXML::Node*` instance.

def to_xml(indent : Int = 2, indent_text = " ", options : SaveOptions = SaveOptions.xml_default) #

Serialize this Node as XML and return a `String` using default options.

See `XML::SaveOptions.xml_default` for default options.

def to_xml(io : IO, indent = 2, indent_text = " ", options : SaveOptions = SaveOptions.xml_default) #

Serialize this Node as XML to io using default options.

See `XML::SaveOptions.xml_default` for default options.

def type #

Returns the type for this Node as `XML::Node::Type`.

def unlink #

Removes the node from the XML document.

def version #

Returns the version of this node's document.

def xml? #

Returns `true` if this is an xml Document node.

def xpath(path, namespaces = nil, variables = nil) #

Searches this node for XPath path. Returns result with appropriate type (`Bool | Float64 | String | XML::NodeSet`).

Raises `XML::Error` on evaluation error.

def xpath_bool(path, namespaces = nil, variables = nil) #

Searches this node for XPath path and restricts the return type to `Bool`.

    require "xml"

    doc = XML.parse("<person></person>")

    doc.xpath_bool("count(//person) > 0") # => true

def xpath_float(path, namespaces = nil, variables = nil) #

Searches this node for XPath path and restricts the return type to `Float64`.

    require "xml"

    doc = XML.parse("<person></person>")

    doc.xpath_float("count(//person)") # => 1.0

def xpath_node(path, namespaces = nil, variables = nil) #

Searches this node for XPath path for nodes and returns the first one. or `nil` if not found

    require "xml"

    doc = XML.parse("<person></person>")

    doc.xpath_node("//person")  # => #<XML::Node:0x2013e80 name="person">
    doc.xpath_node("//invalid") # => nil

def xpath_nodes(path, namespaces = nil, variables = nil) #

Searches this node for XPath path and restricts the return type to `NodeSet`.

    require "xml"

    doc = XML.parse("<person></person>")

    nodes = doc.xpath_nodes("//person")
    nodes.class       # => XML::NodeSet
    nodes.map(&.name) # => ["person"]

def xpath_string(path, namespaces = nil, variables = nil) #

Searches this node for XPath path and restricts the return type to `String`.

    require "xml"

    doc = XML.parse("<person></person>")

    doc.xpath_string("string(/persons/person[1])")