What is XPath (XML Path)?

XML Tutorials - Herong's Tutorial Examples - Version 5.05, by Dr. Herong Yang

XML Tutorials - Herong's Tutorial Examples

∟What is XPath (XML Path)?

This section provides a quick introduction of XPath (XML Path), which is an expression language to produce a value that represents sub structure of an XML document.

What Is XPath (XML Path)? XPath is an expression evaluation language to produce a value that represents sub structure of an XML document.

You can compare XPath with regular expression, which is an expression language to produce a value that represents sub structure of a text string.

You can compare XPath with the DOS path name convention, which is a simple expression language to produce a value that represents a sub structure of a file system.

Writing an XPath expression involves following aspects:

Data types, literals and variables
Evaluation context
Operations
Build-in functions

XPath is used currently in both XSLT and XPointer.

Here are some examples of XPath expressions:

.             Representing the current node
img           Representing child elements named as "img"
@color        Representing the attribute named as "id"
/html         Representing the root element named as "html"
p[1]          Representing the first occurrence of child "p" elements
p[@id=open]   Representing child "p" elements with id="open" attribute

Last update: 2014.

Table of Contents

About This Book

Introduction of XML (eXtensible Markup Language)

XML File Syntax

XML File Browsers

DOM (Document Object Model) Programming Interface

SAX (Simple API for XML) Programming Interface

DTD (Document Type Definition) Introduction

Syntaxes of DTD Statements

Validating an XML Document against the Specified DTD Document Type

XSD (XML Schema Definition) Introduction