XML (.xml)

BackgroundBackground

    MIME type: text/xml
    XML general-purpose markup language and structured document format.
    Primarily used for the exchange of data across different systems in computer networks.
    Uses a hierarchical model for the representation of structured data.
    Stores data in a tree-based structure consisting of markup tags, attributes, and character contents.
    Plain text file, normally encoded as UTF-8.
    XML is an acronym derived from Extensible Markup Language.
    Is a subset of the Standard Generalized Markup Language (SGML).
    Developed since 1996 by the XML Working Group.
    Published in 2001 as W3C standard recommendation RFC 3076.

Import and ExportImport and Export

  • Import["file.xml"] uses a specific converter for XML-based file formats if possible, otherwise it imports the file as generic XML and returns an XMLObject expression.
  • Import["file.xml","XML"] always imports as generic XML.
  • Since both XML and the Wolfram Language represent data as a tree structure, there is a natural mapping from one to the other. The Wolfram Language stores XML data structures as nested XMLElement objects, and an entire XML document as XML data embedded in an XMLObject.
  • Export["file.xml",expr] exports an XMLObject or XMLElement expression to XML.
  • Expressions of types other than XMLObject or XMLElement are exported as ExpressionML.
  • Import["file.xml"] returns an XMLObject expression, representing the entire XML document in symbolic form as a tree of XMLElement expressions.
  • Import by default returns numeric data stored in XML as strings.
  • Export["file.xml",XMLObject[]] or Export["file.xml",XMLElement[]] creates an XML file from a symbolic XML representation.
  • Import["file.xml",elem] imports the specified element from an XML file.
  • Import["file.xml",{elem,suba,subb,}] imports a subelement.
  • Import["file.xml",{{elem1,elem2,}}] imports multiple elements.
  • The import format can be specified with Import["file","XML"] or Import["file",{"XML",elem,}].
  • Import["file.html","XML"] converts HTML to well-formed XML before importing.
  • Export["file.xml",expr, elem] creates an XML file by treating expr as specifying element elem.
  • Export["file.xml",{expr1,expr2,},{{elem1,elem2,}}] treats each as specifying the corresponding .
  • Export["file.xml",expr,opt1->val1,] exports expr with the specified option elements taken to have the specified values.
  • Export["file.xml",{elem1->expr1,elem2->expr2,},"Rules"] uses rules to specify the elements to be exported.
  • See the reference pages for full general information on Import and Export.
  • ImportString and ExportString support the XML format.

ElementsElements

  • General Import elements:
  • "Elements"list of elements and options available in this file
    "Rules"full list of rules for each element and option
    "Options"list of rules for options, properties, and settings
  • Data representation elements:
  • "CDATA"CDATA sections as a list of strings
    "Comments"XML comments as a list of strings
    "EmbeddedDTD"DTD included in the XML document
    "Plaintext"a plain text representation of the file
    "Tags"list of all tags occurring in the file
    "XMLObject"entire document as a symbolic XML expression
    "XMLElement"nested XMLElement objects
  • Import uses the element by default.

OptionsOptions

  • Import options:
  • "AllowRemoteDTDAccess"Truewhether to attempt to retrieve an external DTD over a network
    "AllowUnrecognizedEntities"Automaticwhether to allow parsing to work around unrecognized entities in the XML document
    "IncludeDefaultedAttributes"Falsewhether to fill in default values for attributes
    "IncludeEmbeddedObjects"Noneembedded objects (of and ) to include
    "IncludeNamespaces"Automaticwhether to return fully qualified tag and attribute names
    "NormalizeWhitespace"Automaticwhether to remove leading and trailing whitespace and reduce consecutive spaces to a single space in character data
    "PreserveCDATASections"Falsewhether to preserve character data sections as special objects
    "ReadDTD"Truewhether to read an external DTD
    "ValidateAgainstDTD"Automaticwhether to validate the document against the specified DTD
  • Export options:
  • "AttributeQuoting""'"specifies the delimiter for attribute values
    "ElementFormatting"Automaticindentation of elements and line breaking of long strings in the exported document
    "Entities"Nonerules for replacing characters with named entities
    "NamespacePrefixes"{}namespace prefix designations, of the form

ExamplesExamplesopen allclose all

Basic Examples  (1)Basic Examples  (1)

Import an XML sample file as symbolic XML:

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Show the Import elements available in this file:

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Import all CDATA sections:

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Convert to plain text:

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Get the list of all XML tags that occur in this sample file:

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Introduced in 2002
(4.2)
| Updated in 2008
(7.0)