class XML:: Reader
Overview
XML::Reader
is a parser for XML that iterates a XML document.
require "xml"
reader = XML::Reader.new(<<-XML)
<message>Hello XML!</message>
XML
reader.read
reader.name # => "message"
reader.read
reader.value # => "Hello XML!"
This is an alternative approach to XML.parse
which parses an entire document
into an XML data structure.
XML::Reader
offers more control and does not need to store the XML document
in memory entirely. The latter is especially useful for large documents with
the IO
-based constructor.
WARNING This type is not concurrency-safe.
Defined in:
xml/reader.crxml/reader/type.cr
Constructors
-
.new(str : String, options : XML::ParserOptions = XML::ParserOptions.default)
Creates a new reader from a string.
-
.new(io : IO, options : XML::ParserOptions = XML::ParserOptions.default)
Creates a new reader from an IO.
Instance Method Summary
-
#[](attribute : String) : String
Gets the attribute content for the attribute given by name.
-
#[]?(attribute : String) : String | Nil
Gets the attribute content for the attribute given by name.
-
#attributes_count : Int32
Returns attribute count of the node.
-
#depth : Int32
Returns the current nesting depth of the reader.
-
#empty_element? : Bool
Checks if the node is an empty element.
-
#errors : Array(XML::Error)
Returns the errors reported while parsing.
-
#expand : XML::Node
Expands the node to a
XML::Node
that can be searched with XPath etc. -
#expand? : XML::Node | Nil
Expands the node to a
XML::Node
that can be searched with XPath etc. -
#has_attributes? : Bool
Checks if the node has any attributes.
-
#move_to_attribute(name : String) : Bool
Moves to the
XML::Reader::Type::ATTRIBUTE
with the specified name. -
#move_to_element : Bool
Moves from the
XML::Reader::Type::ATTRIBUTE
to its containingXML::Reader::Type::ELEMENT
. -
#move_to_first_attribute : Bool
Moves to the first
XML::Reader::Type::ATTRIBUTE
of the node. -
#move_to_next_attribute : Bool
Moves to the next
XML::Reader::Type::ATTRIBUTE
of the node. -
#name : String
Returns the name of the node.
-
#next : Bool
Moves the reader to the next node while skipping subtrees.
-
#next_sibling : Bool
Moves the reader to the next sibling node while skipping subtrees.
-
#node_type : XML::Reader::Type
Returns the
XML::Reader::Type
of the node. -
#read : Bool
Moves the reader to the next node.
-
#read_inner_xml : String
Returns the node's XML content including subtrees.
-
#read_outer_xml : String
Returns the XML for the node and its content including subtrees.
-
#to_unsafe : LibXML::XMLTextReader
Returns a reference to the underlying
LibXML::XMLTextReader
. -
#value : String
Returns the text content of the node.
Instance methods inherited from class Reference
==(other : self)==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup, hash(hasher) hash, initialize initialize, inspect(io : IO) : Nil inspect, object_id : UInt64 object_id, pretty_print(pp) : Nil pretty_print, same?(other : Reference) : Bool
same?(other : Nil) same?, to_s(io : IO) : Nil to_s
Constructor methods inherited from class Reference
new
new,
unsafe_construct(address : Pointer, *args, **opts) : self
unsafe_construct
Class methods inherited from class Reference
pre_initialize(address : Pointer)
pre_initialize
Instance methods inherited from class Object
! : Bool
!,
!=(other)
!=,
!~(other)
!~,
==(other)
==,
===(other : JSON::Any)===(other : YAML::Any)
===(other) ===, =~(other) =~, as(type : Class) as, as?(type : Class) as?, class class, dup dup, hash(hasher)
hash hash, in?(collection : Object) : Bool
in?(*values : Object) : Bool in?, inspect(io : IO) : Nil
inspect : String inspect, is_a?(type : Class) : Bool is_a?, itself itself, nil? : Bool nil?, not_nil!(message)
not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, responds_to?(name : Symbol) : Bool responds_to?, tap(&) tap, to_json(io : IO) : Nil
to_json : String to_json, to_pretty_json(indent : String = " ") : String
to_pretty_json(io : IO, indent : String = " ") : Nil to_pretty_json, to_s(io : IO) : Nil
to_s : String to_s, to_yaml(io : IO) : Nil
to_yaml : String 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
Macros inherited from class Object
class_getter(*names, &block)
class_getter,
class_getter!(*names)
class_getter!,
class_getter?(*names, &block)
class_getter?,
class_property(*names, &block)
class_property,
class_property!(*names)
class_property!,
class_property?(*names, &block)
class_property?,
class_setter(*names)
class_setter,
def_clone
def_clone,
def_equals(*fields)
def_equals,
def_equals_and_hash(*fields)
def_equals_and_hash,
def_hash(*fields)
def_hash,
delegate(*methods, to object)
delegate,
forward_missing_to(delegate)
forward_missing_to,
getter(*names, &block)
getter,
getter!(*names)
getter!,
getter?(*names, &block)
getter?,
property(*names, &block)
property,
property!(*names)
property!,
property?(*names, &block)
property?,
setter(*names)
setter
Constructor Detail
Instance Method Detail
Gets the attribute content for the attribute given by name.
Raises KeyError
if attribute is not found.
Expands the node to a XML::Node
that can be searched with XPath etc.
The returned XML::Node
is only valid until the next call to #read
.
Raises a XML::Error
if the node could not be expanded.
Expands the node to a XML::Node
that can be searched with XPath etc.
The returned XML::Node
is only valid until the next call to #read
.
Returns nil
if the node could not be expanded.
Returns a reference to the underlying LibXML::XMLTextReader
.