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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