Fall 2006

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Florida Atlantic UniversityDepartment of
Computer Science Engineering
COP 4814 Web Services Dr. Roy Levow Part 4 - XML
Fall 2006
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XML, XPath, XSLT

• XML support generally limited to IE and Firefox
• XML in IE
• Microsoft.XmlDom in IE4.0
• MSXML ActiveX in IE 5.0
• But only on Windows not on MAC
• Text uses createDocument() for cross-IE
  compatability
• XML DOM object created from string

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XML DOM Navigation

• DOM object properties
• childNodes, firstChild, lastChild,
• parentNode, nextSibling, previousSibling,
• nodeName, nodeType, nodeValue
• text, attributes
• xml
• ownerDocument root node
• Navigate tree with these functions

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IE XML DOM Navigation Examples

• Examples IE DOM
• DOM creation
• Get Elements by Tag Name
• Create Node
• Insert Node
• Remove Child
• Replace Child

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IE XML DOM Error Handling

• Creates and propagates exception object
  parseError
• parseError object provides details
• errorCode, reason
• filePos, line, linePos
• srcText
• url

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XML DOM in Firefox

• Uses createDocument() method to generate DOM
  object
• Empty
• From string
• From url
• load() method loads from a url
• String version of XML subtree is produced by
  XMLSerializer object

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XML DOM in Firefox - 2

• Error handling
• Firefox produces an error document
• Not the error object of IE
• It can be parsed to get the same information

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Firefox XML DOM - 3

• Examples Firefox DOM
• DOM Dreation
• DOM Parser
• Get text
• Serialize
• Error handling

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Cross-Browser XML

• Requires library to create standard calls for
  operations
• Text provides zXml library
• zXmlDom.createDocument()
• Examples Cross-Browser DOM
• Processing Book List

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XML Namespaces

• XML uses namespace concept to resolve naming
  conflicts between documents from different
  sources
• Tag name has form nstagName
• Declared as xmlsnns-prefixnsURI
• URI has same syntax as URL but need not be real
  address
• Should be unique
• Declarations in root tag of document

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XPath

• XPath expressions
• Context node is partial path from which selection
  begins
• book/author this parent-child sequence
• Selection pattern specifies which nodes to
  include
• book_at_isbn0010001001
• Expressions have own syntax and can be quite
  complex

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XPath in IE and Firefox

• IE uses two functions
• selectSingleNode()
• selectNodes()
• Examples IE XPath
• Firefox uses two objects
• XPathEvaluator
• XPathResult
• Examples Firefox XPath

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Cross-Browser XPath

• Use zXml library
• Same functions as IE
• Examples Cross-Browser XPath

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XSL Transformations

• Transformation is done with
• xslstylesheet with XML specific elements
• xsltemplate to select XMLnodes to process
• xslvariable to select attributes from nodes
• Examples XSLT

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XSLT in IE

• Browser becomes an issue when DOM is used in
  conjunction with XSLT
• Must create ActiveX XSLTemplate object
• Create processor object from template object
• transform() method does transformation
• Result is output property of processor
• Examples XSLT in IE

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Cross-Browser XSLT

• Requires library
• Text provides this in zXml
• Syntax similar to Firefox
• Example Best Picks Revisited

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XSLT in Firefox

• First load XML and XSL into DOM objects
• Create XSLTProcessor
• Import XSL stylesheet
• Transform XmlDOM document or fragment
• Examples XSL in Firefox