Matakuliah
Tahun
: T0063 – Pemrograman Visual
: 2009
Accessing Data
Using XML
CHAPTER NINE
Introduction
• The eXtensible Markup Language (XML) is a language
used to represent data in a form that does not rely on any
particular proprietary technology.
• XML Schema provides a way of defining and validating
XML documents.
• eXtensible Stylesheet Language (XSL) and eXtensible
Stylesheet Language Transforms
(XSLT) is another useful technology associated with XML.
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Introduction (cont.)
• This capability enables you to take a single XML
document and transform it into a variety of different
versions for specific uses.
• A number of classes within Visual Basic .NET provide
methods that work directly with XML.
• Microsoft’s .NET initiative uses XML as its foundation
data technology.
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Objectives
• Understand what XML is and how it is used within
business-to-business transactions.
• Understand XML Schemas and XSL Transforms and
how they are used within the context of XML.
• Read and process data that are stored in an XML
document.
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Objectives (cont.)
• Read data from a relational database and transform
them into their equivalent XML.
• Transform one XML document into a new XML document
using an XSLT document.
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9.1 An XML Primer
• What is XML?
– XML provides a technology-neutral way to represent
data.
– XML is rapidly becoming the data format “standard”
for the exchange of data on the Internet.
– Data content and data presentation are separate.
– Data represent what is called a tree.
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9.1 An XML Primer (cont.)
• XML Syntax
– The language is case sensitive.
– There is one and only one root node.
– All elements have a start tag and an end tag.
– Tags must be nested correctly.
– Attributes must be quoted.
• An XML document is well formed if you follow the above
rules.
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9.1 An XML Primer (cont.)
– Namespaces
• A namespace defines a point of reference.
– Change the element tag by adding a prefix and
a colon to the tag.
– Ex. <furn:table> and <tax:table>.
• Can differentiate two tags within the same
document.
• Syntax: xmlns:name = “uri”
• The uri (Uniform Resource Identifier) is a unique
identifier.
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9.1 An XML Primer (cont.)
– Document Prolog
• Indicates that the document is XML as well as
other things such as document type, entity
definitions and other processing instructions.
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9.1 An XML Primer (cont.)
• XML Schemas
– Rules that define legal elements, tags, and content.
– Used to determine the validity of a document.
– Industry specific XML schemas are being developed.
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9.1 An XML Primer (cont.)
• Styling XML
– Extensible Stylesheet Language Transforms (XSLT)
provide a way to transform one XML document to
another XML document.
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9.2 Creating XML Documents and XML
Schemas Using Visual Basic .NET
• Creating an XML Schema
– Add an XML Schema to a project by selecting Add
New Item from the File menu.
– Use tools from the Toolbox to create the schema.
– Save the Schema definition.
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9.2 Creating XML Documents and XML
Schemas Using Visual Basic .NET (cont.)
• Creating an XML Document
– Complete the examples listed below in your textbook:
• Example 9.1 Using Simple and Complex Data
Types in XML Schemas.
• Example 9.2 Creating Nested Relationships in an
XML Schema.
• Example 9.3 Creating Tables with Relationships in
an XML Schema.
• Example 9.4 Transforming XML using XSLT.
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9.3 Using ADO.NET with XML
• ADO.NET provides a number of useful classes and
methods to work directly with XML documents.
– Data are already in XML form.
• This section provides a number of examples that
demonstrate XML capabilities of the ADO.NET
framework.
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9.3 Using ADO.NET with XML (cont.)
• Complete the following examples listed below in your
textbook:
– Example 9.5 Processing an XML Document.
– Example 9.6 Converting Relational DB Data into
XML.
– Example 9.7 Using XML and XSLT to Transform Data
from a Relational Database.
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