535.  XML Parsing Using Visual Basic

Rev. 1.0

 

This module introduces the MSXML 4 parser and the two main Visual Basic APIs for parsing XML documents: SAX and the DOM. Students learn the basic MSXML architecture and how to create parsers that expose SAX or DOM APIs in VB code, and how to configure parsers according to the SAX features and properties specification. SAX parsing is covered, working from simple SAX event handling through patterns for understanding document content from event sequences, to error handling and document validation. Students then learn how to read document information using the DOM’s tree model and API, and move on to using the DOM to modify and to create new documents and information nodes.

 

LEARNING OBJECTIVES

 

·         Understand the use of SAX and DOM APIs for XML parsing.

·         Use MSXML to write XML parsing code in Visual Basic.

·         Parse element and attribute content, processing instructions, and other document information using SAX.

·         Parse documents using the DOM.

·         Modify, create and delete information in an XML document using the DOM.

 

Course Duration:  2 days

 

Prerequisites:  Experience in Visual Basic Programming. Basic knowledge, not necessarily fluency, in reading and writing well-formed XML documents, and an understanding of the concepts of valid documents and XML vocabularies. Both DTDs and XML Schema are used in the module, and structural understanding of either will be very helpful.

 

1.      The Microsoft XML Parser (MSXML)

Pure XML

Parsing XML

SAX and DOM

Comparison of SAX and DOM

What the W3C Says

What the W3C Doesn’t Say

MSXML Introduction

MSXML Deployment

 

2.      The Simple API for XML (SAX)

Origins of SAX

The SAX Parser

The SAXReader CoClass

The SAX Event Model

The SAX Event Model – Interactions

The ContentHandler Interface

Reading Document Content

Handling Namespaces

SAX Features for Namespaces

Parsing Attributes

Error Handling

Handling Processing Instructions

DTD Validation

Schema Validation

XML for Object Persistence

Serialization with SAX

 

3.      The Document Object Model (DOM)

Origins of the DOM

DOM Levels

DOM2 Structure

The DOMDocument CoClass

DOM Tree Model

DOM Interfaces

Document, Node and NodeList Interfaces

Element and Text Interfaces

Finding Elements By Name

Walking the Child List

The Attribute Interface

Namespaces and the DOM

Error Handling

The ProcessingInstruction Interface

The DOM and the XML InfoSet

Combining SAX and DOM

Object Serialization with the DOM

 

4.      Manipulating XML Information with the DOM

Modifying Documents

Modifying Elements

Modifying Attributes

Managing Children

Cloning

Splitting Text and Normalizing

Creating New Documents

Object Persistence with the DOM

Adapting Object Models to the DOM

 

Learning Resources

 

Quick Reference: XML and DTD Grammar

 

System Requirements

 

Software for this module can be installed and run on Windows systems only. Required tools are Visual Basic 6 and the MSXML parser, version 4.0 or higher.

 

Hardware requirements are modest: a good minimal system for this module would have a Pentium 500MHz or equivalent CPU, 256 meg of RAM and at least 500 megabytes of free disk space for tools installation and lab software.