CheatSheet for XPATH
Descendant selectors
h1 | //h1 | |
div p | //div//p | |
ul > li | //ul/li | |
ul > li > a | //ul/li/a | |
div > * | //div/* | |
:root | / | |
:root > body | /body |
Attribute selectors
#id | //[@id="id"] | |
.class | //[@class="class"] … | |
input[type="submit"] | //input[@type="submit"] | |
a#abc[for="xyz"] | //a[@id="abc"][@for="xyz"] | |
a[rel] | //a[@rel] | |
a[href^='/'] | //a[starts-with(@href, '/')] | |
a[href$='pdf'] | //a[ends-with(@href, '.pdf')] | |
a[href~='://'] | //a[contains(@href, '://')] … |
Order selectors
ul > li:first-child | //ul/li[1] | |
ul > li:nth-child(2) | //ul/li[2] | |
ul > li:last-child | //ul/li[last()] | |
li#id:first-child | //li[@id="id"][1] | |
a:first-child | //a[1] | |
a:last-child | //a[last()] |
Siblings
h1 ~ ul | //h1/following-sibling::ul | |
h1 + ul | //h1/following-sibling::ul[1] | |
h1 ~ #id | //h1/following-sibling::[@id="id"] |
jQuery
$('ul > li').parent() | //ul/li/.. | |
$('li').closest('section') | //li/ancestor-or-self::section | |
$('a').attr('href') | //a/@href | |
$('span').text() | //span/text() |
Other things
h1:not([id]) | //h1[not(@id)] | |
Text match | //button[text()="Submit"] | |
Text match (substring) | //button[contains(text(),"Go")] | |
Arithmetic | //product[@price > 2.50] | |
Has children | //ul[*] | |
Has children (specific) | //ul[li] | |
Or logic | //a[@name or @href] | |
Union (joins results) | //a | //div |
Class check
Xpath doesn’t have the “check if part of space-separated list” operator, so this is the workaround (source):
//div[contains(concat(' ',normalize-space(@class),' '),' foobar ')]
Expressions
Prefixes
Begin your expression with any of these.
// anywhere | //hr[@class='edge'] |
./ relative | ./a |
/ root | /html/body/div |
Axes
Separate your steps with
/
. Use two (//
) if you don’t want to select direct children./ child | //ul/li/a |
// descendant | //[@id="list"]//a |
Steps
//div
//div[@name='box']
//[@id='link']
They can also be these other things.
//a/text() #=> "Go home"
//a/@href #=> "index.html"
//a/* #=> All a's child elements
Predicates
Predicates ([...]
)
Restricts a nodeset only if some condition is true. They can be chained.
//div[true()]
//div[@class="head"]
//div[@class="head"][@id="top"]
Operators
Use comparison and logic operators to make conditionals.
# Comparison
//a[@id = "xyz"]
//a[@id != "xyz"]
//a[@price > 25]
# Logic (and/or)
//div[@id="head" and position()=2]
//div[(x and y) or not(z)]
Using nodes
You can use nodes inside predicates.
# Use them inside functions
//ul[count(li) > 2]
//ul[count(li[@class='hide']) > 0]
# This returns `
` that has a `
` child
//ul[li]
Indexing
Use
[]
with a number, or last()
or position()
.//a[1] # first
//a[last()] # last
//ol/li[2] # second
//ol/li[position()=2] # same as above
//ol/li[position()>1] # :not(:first-child)
Chaining order
Order is significant, these two are different.
a[1][@href='/']
a[@href='/'][1]
Nesting predicates
This returns
if it has an
if it has an
descendant with id='hi'
.//section[//h1[@id='hi']]
Functions
Node functions
name() # //[starts-with(name(), 'h')]
text() # //button[text()="Submit"]
# //button/text()
lang(str)
namespace-uri()
count() # //table[count(tr)=1]
position() # //ol/li[position()=2]
Boolean functions
not(expr) # button[not(starts-with(text(),"Submit"))]
String functions
contains() # font[contains(@class,"head")]
starts-with() # font[starts-with(@class,"head")]
ends-with() # font[ends-with(@class,"head")]
concat(x,y)
substring(str, start, len)
substring-before("01/02", "/") #=> 01
substring-after("01/02", "/") #=> 02
translate()
normalize-space()
string-length()
Type conversion
string()
number()
boolean()
Axes
Using axes
Steps of an expression are separated by
/
, usually used to pick child nodes. That’s not always true: you can specify a different “axis” with ::
.//ul/li # ul > li
//ul/child::li # ul > li (same)
//ul/following-sibling::li # ul ~ li
//ul/descendant-or-self::li # ul li
//ul/ancestor-or-self::li # $('ul').closest('li')
Child axis
This is the default axis. This makes
//a/b/c
work.# both the same
//ul/li/a
//child::ul/child::li/child::a
# both the same
# this works because `child::li` is truthy, so the predicate succeeds
//ul[li]
//ul[child::li]
# both the same
//ul[count(li) > 2]
//ul[count(child::li) > 2]
Descendant-or-self axis
//
is short for the descendant-or-self::
axis.# both the same
//div//h4
//div/descendant-or-self::h4
# both the same
//ul//[last()]
//ul/descendant-or-self::[last()]
Other axes
There are other axes you can use.
Axis | Abbrev | Description |
---|---|---|
ancestor | ||
ancestor-or-self | ||
attribute | @ | @href is short for attribute::href |
child | div is short for child::div | |
descendant | ||
descendant-or-self | // | // is short for /descendant-or-self::node()/ |
namespace | ||
self | . | . is short for self::node() |
parent | .. | .. is short for parent::node() |
following | ||
following-sibling | ||
preceding | ||
preceding-sibling |
Unions
Use
|
to join two expressions.//a | //span
More examples
//* # all elements
count(//*) # count all elements
(//h1)[1]/text() # text of the first h1 heading
//li[span] # find a
with an inside it
# ...expands to //li[child::span]
//ul/li/.. # use .. to select a parent
# Find a that directly contains h1#section-name
//section[h1[@id='section-name']]
# Find a that contains h1#section-name
# (Same as above, but use descendant-or-self instead of child)
//section[//*[@id='section-name']]
# like jQuery's $().closest('.box')
./ancestor-or-self::[@class="box"]
# Find - and check its attributes
//item[@price > 2*@discount]
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