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"] |
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://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
A step may have an element name (div) and predicates ([...]). Both are optional.//div
//div[@name='box']
//[@id='link']
They can also be these other things.
//a/text() | For eg: "Go home" |
//a/@href | For eg: "index.html" |
//a/* | Get 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 `<ul>` that has a `<li>` child
//ul[li]
Indexing
Use [] with a number, or last() or position().//a[1] # first <a>
//a[last()] # last <a>
//ol/li[2] # second <li>
//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 <section> if it has an <h1> descendant with id='hi'.//section[//h1[@id='hi']]
Functions
Node functions
name() # //[starts-with(name(), 'h')]
text() # //button/text()
# //button[text()="Submit"] -- This will return Element with 'EXACT' text
# //*[contains(text(),'Sometext')] -- This is for Element 'CONTAINING' the String
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. Different “axis” can be represented with :: as well//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 axes
This is the default axis. This makes //a/b/c work.
# both are the same
//ul/li/a
//child::ul/child::li/child::a
//ul/li/a
//child::ul/child::li/child::a
# this works because 'child::li' is valid, so the predicate succeeds
//ul[li]
//ul[child::li]
//ul[li]
//ul[child::li]
# both are the same
//ul[count(li) > 2]
//ul[count(child::li) > 2]
//ul[count(li) > 2]
//ul[count(child::li) > 2]
Descendant-or-self axis
// is short for descendant-or-self:: axis# both are the same
//div//h4
//div/descendant-or-self::h4
# both are the same
//ul//[last()]
//ul/descendant-or-self::[last()]
//ul//[last()]
//ul/descendant-or-self::[last()]
Other axes
There are other axes that can be used.
Axis
|
Abbreviation
|
Description
|
ancestor
|
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
|
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 <li> with an <span> inside it # ...expands to //li[child::span] //ul/li/.. # use .. to select a parent
# Find a <section> that directly contains h1#section-name //section[h1[@id='section-name']]
# Find a <section> 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 <item> and check its attributes //item[@price > 2*@discount]
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