xpath Getting started with xpath
Remarks
XPath is a language for addressing parts of an XML document.
It is used in XSLT and is a subset of XQuery. Libraries are available for most other programming languages as well.
XPath is an international standard with specifications published by W3C:
- XPath 1.0: XML Path Language (XPath), Version 1.0
- XPath 2.0: XML Path Language (XPath) 2.0 (Second Edition)
- XPath 3.0: XML Path Language (XPath) 3.0
Versions
| Version | Release Date |
|---|---|
| 1.0 | 1999-12-16 |
| 2.0 | 2007-01-23 |
| 3.0 | 2014-04-08 |
| 3.1 (W3C Candidate Recommendation) | 2015-12-17 |
Common HTML Operations
If the input HTML DOM is
<html>
<body>
<a>link</a>
<div class='container' id='divone'>
<p class='common' id='enclosedone'>Element One</p>
<p class='common' id='enclosedtwo'>Element Two</p>
</div>
</body>
</html>
Find an element with a specific id in the entire page
//*[@id='divone'] # Returns <div class='container' id='divone'>
Find an element with a specific id in a particular path
/html/body/div/p[@id='enclosedone'] # Returns <p class='common' id='enclosedone'>Element One</p>
Select an element with a particular id & class
//p[@id='enclosedone' and @class='common'] # Returns <p class='common' id='enclosedone'>Element One</p>
Select the text of a particular element
//*[@id='enclosedone']/text() # Returns Element One
Sample XML (without namespaces)
Here is some sample XML against which example XPaths can be written:
<r>
<e a="1"/>
<f a="2" b="1">Text 1</f>
<f/>
<g>
<i c="2">Text 2</i>
Text 3
<j>Text 4</j>
</g>
</r>
Select an element
For the sample XML (without namespaces):
This XPath,
/r/e
will select this element:
<e a="1"/>
Select text
For the sample XML (without namespaces):
This XPath,
/r/f/text()
will select the text node with this string value:
"Text 1"
And this XPath,
string(/r/f)
will return the string value of f , which is also:
"Text 1"
Testing Xpaths in browser console
A quick way to test your xpath is in your browser developer tool console.
Format is
$x('//insert xpath here')
$ - specifies it is a selector.
x - specifies it is using xpaths
Example:
$x("//button[text() ='Submit']")
When this command is entered it will return all occurrences of elements that are buttons with text equal to Submit.
