Kwareji XPath

XPath gana amfani da expression path a cikin dacewa XML don a cikin dacewa koyi koyi ko koyi koyi na koyi koyi. Koyi koyi a cikin dacewa gana amfani da path (path) ko koyi koyi (steps).

XML instance document

A cikakata dacewa abin sha a cikin koyi koyi na koyi koyi.

<?xml version="1.0" encoding="ISO-8859-1"?>
<bookstore>
<book>
  <title lang="eng">Harry Potter</title>
  <price>29.99</price>
</book>
<book>
  <title lang="eng">Learning XML</title>
  <price>39.95</price>
</book>
</bookstore>

A zamma dominan dacewa koyi koyi.

XPath gana amfani da expression path a cikin dacewa XML, kuma a cikin dacewa koyi koyi a cikin dacewa, kuma a cikin koyi koyi.

A cikakata dacewa koyi koyi na abin sha da koyi koyi na abin sha a cikin koyi koyi.

Expression Ba'amfani
nodename A zamma dominan dacewa dacewa ka a cikakata abin sha.
/ A zamma dominan dacewa abin sha dacewa ka a kara.
// A zamma dominan dacewa abin sha a cikin dacewa, kowacey a baiya ka a kara.
. A zamma dominan dacewa abin sha.
.. A zamma dominan dacewa abin sha na abin sha a baiya.
@ A zamma dominan dacewa abin sha.

Tasiri

A cikakata dacewa koyi koyi da abin sha a cikin tabbatta, a cikin kundin abin sha, a cikin kundin abin sha.

Babirin Yada Nantali
bookstore A zamma dominan dacewa dacewa ka a cikakata bookstore.
/bookstore

A zamma dominan dacewa bookstore.

Kanamawa: Kowa ce kawo wajen koyi /, kowa jiyarar ce a zama jiyarar shekarin shekarin shekarin zuwa dacewa abin sha.
bookstore/book A zamma dominan dacewa book a cikakata bookstore.
//book A zamma dominan dacewa book a cikakata dacewa ka a baiya ka a kara.
bookstore//book A zamma dominan dacewa book a cikakata bookstore, kowacey a baiya ka a kara.
//@lang Gyiyi kowane halittu na sunan lang.

Mai kiyashin (Predicates)

Mai kiyashin zai iya amfani don nemi abu na zama ko abu na zama tare da wata kiyashin zama.

Mai kiyashin zai iya kawo cikin kwararrun.

Tasiri

Nin da dace wa tabi, a dace wa tabi kuma nantali na yawa da yawa da kuma nantali na yawa:

Babirin Yada Nantali
/bookstore/book[1] Gyiyi abubu na book na farko da yau suna a cikin bookstore.
/bookstore/book[last()] Gyiyi abubu na book na farko da yau suna a cikin bookstore.
/bookstore/book[last()-1] Gyiyi abubu na book na farko da yau suna a cikin bookstore.
/bookstore/book[position()<3] Gyiyi abubu na book na farko da yau suna a cikin bookstore.
//title[@lang] Gyiyi dukkan title zirin tare da halittu na sunan lang.
//title[@lang='eng'] Gyiyi dukkan title zirin tare da halittu na lang zai iya kawo.
/bookstore/book[price>35.00] Gyiyi abubu na book zama a cikin bookstore, tare da price zirin kai sake kiyashin 35.00.
/bookstore/book[price>35.00]/title Gyiyi abubu na book zama a cikin bookstore, tare da price zirin kai sake kiyashin 35.00.

Gyiyi abubu na zama.

Kabirin XPath zai iya amfani don gyiyi abubu na XML na zama zai iya kawo.

Kabara Ba'amfani
* Dacewa kowane abu.
@* Dacewa kowane abu da yana da halittu.
node() Dacewa kowane nau'war abu.

Tasiri

Nin da dace wa tabi, a dace wa tabi kuma nantali da yawa da yawa da kuma nantali na yawa:

Babirin Yada Nantali
/bookstore/* Gyiyi dukkan zirin zama suna a cikin bookstore.
//* Gyiyi dukkan zirin dake a cikin dokar.
//title[@*] Gyiyi dukkan title zirin tare da halittu.

Gyiyi yawa na yada

A cikin yadda a zaɗaɗɗa yin amfani da mai kiyashin “|” a cikin babirin yada, a kai sake zartarwa na yawa na yada.

Tasiri

Nin da dace wa tabi, a dace wa tabi kuma nantali da yawa da yawa da kuma nantali na yawa:

Babirin Yada Nantali
//book/title | //book/price Gyiyi a zirin book dona da za yin title da price zirin.
//title | //price 选取文档中的所有 title 和 price 元素。
/bookstore/book/title | //price 选取属于 bookstore 元素的 book 元素的所有 title 元素，以及文档中所有的 price 元素。