APath

一、node

expression	description
node	select all children nodes of this node
/	select from root node
//	select the document node from the current matched node,regardless of their position
.	select current node
..	select the parent node of current node
@	select properties

 

 

 

 

 

 

 

 

二、predicate

expression	implication
/bookstore/book[1]	select the first book element belongs to bookstore
/bookstore/book[last()]	select the lastbook element belongs to bookstore
/bookstore/book[position()<3]	select the first two book elements belongs to bookstore
//title[@lang]	choose elements of title with lang property

 

 

 

 

 

 

三、wildcard

expression	description	usage	specification
*	match any node	xpath("/div/*")	select all children nodes under div node
@*	match nodes with any property	xpath("/div[@*]")	select all node with properties
node()	match nodes of any type	xpath("//div[@class=\"tb_cls\"]").node()	select all div tags which class property is tb_cls

 

 

 

 

 

四、multiple path selection

usage	specification
xpath("//book/title*|*//book/price")	select all title elements and price elements of book
xpath("//title|//price")	select all title elements and price elements in the document

 

 

 

 

五、xpath axis

expression	description	usage	illustration
ancestor	select all ancestor nodes of current node	xpath("//div[@id=\"123\"]/ancestor::*")	select all ancestor nodes that tags name is div and id property is 123
ancestor-or-self	select all ancestor node of current node and itself	xpath("//div[@id=\"123\"]/ancestor-or-self::*")	select all ancestor nodes and itself that tags name is div and id property is 123
attribute	select all attributs of current node	xpath("//div[@id=\"123\"]/attribute::class")	select class attribute name that tags name is div and id property is 123
child	select all child nodes of current node	xpath("//div[@id=\"123\"]/child::book")	select all child book nodes that tags name is div and id property is 123
descendant	...	xpath("./descendant::*")	...
following	...	xpath("./following::*")	...
parent	...	xpath("./parent::*")	...
preceding	...	xpath("//div[@id=\"123\"]/preceding::*")	...
preceding-sibling	...	xpath("//div[@id=\"123\"]/preceding-sibling::*")	...
self	...	xpath("./self::*")	...

 

 

 

 

 

 

 

 

 

 

 

 

六、operators

expression	description	usage	illustration
+	...	...	...
-	...	...	...
*	...	...	...
div	...	...	...
=	...	...	...
!=	...	...	...
<	...	...	...
<=	...	...	...
>	...	...	...
>=	...	...	...
or	...	...	...
and	...	...	...
mod	...	...	...

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

七、functions

expression	description	usage	illustration
starts-with()	...	xpath("//div[starts-with(@id,\"ma\")]")	...
contains()	...	xpath("//div[contains(@id,\"ma\")]")	...
and	...	xpath("//div[contains(@id,\"ma\")] and contains(@id,\"in\")")	...
text()	...	xpath("//div[contains(text(),\"ma\")]")	...