Mfano wa XPath

Katika kisiini hii, tunasoma mafanikio ya kiingilio cha XPath kwa mafanikio ya kawaida.

Mafanikio ya XML

Tunategemea hizi mafanikio hivi chini tunaingia kwa mafanikio ya hii taarifa ya XML:

"books.xml" :

<?xml version="1.0" encoding="ISO-8859-1"?>
<bookstore>
<book category="COOKING">
  <title lang="en">Everyday Italian</title>
  <author>Giada De Laurentiis</author>
  <year>2005</year>
  <price>30.00</price>

<book category="CHILDREN">
  <title lang="en">Harry Potter</title>
  <author>J K. Rowling</author>
  <year>2005</year>
  <price>29.99</price>

<book category="WEB">
  <title lang="en">XQuery Kick Start</title>
  <author>James McGovern</author>
  <author>Per Bothner</author>
  <author>Kurt Cagle</author>
  <author>James Linn</author>
  <author>Vaidyanathan Nagarajan</author>
  <year>2003</year>
  <price>49.99</price>

<book category="WEB">
  <title lang="en">Learning XML</title>
  <author>Erik T. Ray</author>
  <year>2003</year>
  <price>39.95</price>

在您的浏览器中查看此 "books.xml" 文件。

加载 XML 文档

所有现代浏览器都支持使用 XMLHttpRequest 来加载 XML 文档的方法。

针对大多数现代浏览器的代码：

var xmlhttp=new XMLHttpRequest()

针对古老的微软浏览器（IE 5 和 6）的代码：

var xmlhttp=new ActiveXObject("Microsoft.XMLHTTP")

选取节点

不幸的是，Internet Explorer 和其他处理 XPath 的方式不同。

在我们的例子中，包含适用于大多数主流浏览器的代码。

Internet Explorer huzungumza kwa methodi ya selectNodes() kuachaga node za faili ya XML:

xmlDoc.selectNodes(xpath);

Firefox, Chrome, Opera na Safari huzungumza kwa methodi ya evaluate() kuachaga node za faili ya XML:

xmlDoc.evaluate(xpath, xmlDoc, null, XPathResult.ANY_TYPE,null);

Chagula tabia za title zote

Mfano hii inachagula tabia za title zote:

/bookstore/book/title

Tukutufe Kwa Basi

Chagula title ya book ya kwanza

Mfano hii inachagula title ya kwanza ya elementi ya book kwenye bookstore:

/bookstore/book[1]/title

Tukutufe Kwa Basi

Hakuna mafungo. Mfano hii inapata matokeo ya kawaida kwenye IE na mengineo ya kawaida.

IE5 na viwango vyengineza [0] kama mwanakili wa kwanza, kwa sababu ya mtumaini wa W3C, inafikia [1].

Kuwa kumaliza mafungo ya [0] na [1] katika IE5+, inaweza kuweka chaguo la lugha kwa XPath (SelectionLanguage).

Mfano hii inachagula title ya kwanza ya elementi ya book kwenye bookstore:

xml.setProperty("SelectionLanguage","XPath");
xml.selectNodes("/bookstore/book[1]/title");

Tukutufe Kwa Basi

Chagula tena kwa siku zote

Mfano hii inachagula tabia za price zote kwenye node za price:

/bookstore/book/price/text()

Tukutufe Kwa Basi

Chagula tena kwa price taka 35

下面的例子选取价格高于 35 的所有 price 节点：

/bookstore/book[price>35]/price

Tukutufe Kwa Basi

选取价格高于 35 的 title 节点

下面的例子选取价格高于 35 的所有 title 节点：

/bookstore/book[price>35]/title

Tukutufe Kwa Basi