通过属性值获取元素 [英] get elements by attribute value

问题描述

我通过 webservices 在 Javascript 发送请求，我收到的响应是这样的： p>

I am sending a request via webservices in Javascript and the response i am receiving is like this:

<ListOfBook>
<Book>
    <Id>ACIA-11QWTKX</Id>
    <ListOfBookUser recordcount="0" lastpage="true">
    </ListOfBookUser>
</Book>
<Book>
    <Id>ACIA-ANC0CC</Id>
    <ListOfBookUser recordcount="1" lastpage="true">
        <BookUser>
            <BookId>ACIA-ANC0CC</BookId>
            <BookName>TKSP_GLOBAL</BookName>
        </BookUser>
        </ListOfBookUser>
</Book>                             
<Book>
    <Id>ACIA-ANC0CF</Id>
    <ListOfBookUser recordcount="0" lastpage="true">
    </ListOfBookUser>
</Book>
<Book>
    <Id>ACIA-EUMCH5</Id>
    <ListOfBookUser recordcount="1" lastpage="true">
        <BookUser>
            <BookId>ACIA-EUMCH5</BookId>
            <BookName>TKSP_MADRID_CENTRO_SUR</BookName>
        </BookUser>
    </ListOfBookUser>
</Book>

如你所见，有一些元素具有< BookUser> 的小孩&​​gt; ，还有其他没有这个孩子的元素。

As you can see there are some elements of <Book> that have a child <BookUser> and there are other elements that doesn't have this child.

我需要一种方法来提取具有< BookUser> < Book> $ c> child with 正则表达式， DOM 或 Xpath 。任何建议？

I need a way to extract elements of <Book> that have the <BookUser> child with regular expressions, DOM or Xpath. Any suggestions please ?

推荐答案

您可以使用XPath与 // Book [ListOfBookUser / BookUser ] ：

You can use XPath with an expression like //Book[ListOfBookUser/BookUser]:

var xmlMarkup = `<ListOfBook>
<Book>
    <Id>ACIA-11QWTKX</Id>
    <ListOfBookUser recordcount="0" lastpage="true">
    </ListOfBookUser>
</Book>
<Book>
    <Id>ACIA-ANC0CC</Id>
    <ListOfBookUser recordcount="1" lastpage="true">
        <BookUser>
            <BookId>ACIA-ANC0CC</BookId>
            <BookName>TKSP_GLOBAL</BookName>
        </BookUser>
        </ListOfBookUser>
</Book>                             
<Book>
    <Id>ACIA-ANC0CF</Id>
    <ListOfBookUser recordcount="0" lastpage="true">
    </ListOfBookUser>
</Book>
<Book>
    <Id>ACIA-EUMCH5</Id>
    <ListOfBookUser recordcount="1" lastpage="true">
        <BookUser>
            <BookId>ACIA-EUMCH5</BookId>
            <BookName>TKSP_MADRID_CENTRO_SUR</BookName>
        </BookUser>
    </ListOfBookUser>
</Book>
</ListOfBook>`;

var xmlDoc = new DOMParser().parseFromString(xmlMarkup, 'application/xml');
var bookSnapshot = xmlDoc.evaluate('//Book[ListOfBookUser/BookUser]', xmlDoc, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
for (var i = 0, l = bookSnapshot.snapshotLength; i < l; i++) {
  var book = bookSnapshot.snapshotItem(i);
  var id = xmlDoc.evaluate('Id', book, null, XPathResult.FIRST_ORDERED_NODE_TYPE, null).singleNodeValue;
  if (id != null) {
    console.log(id.textContent);
  }
}

为了简洁起见， -line字符串文字分隔符仅在实际的浏览器中实现，但在Mozilla，Chrome，Safari和Edge中的DOM实现中支持XPath API。

For brevity of the sample, I have used the multi-line string literal delimiters `` only implemented in actual browsers, but the XPath API is supported in DOM implementations in Mozilla, Chrome, Safari and Edge.

这篇关于通过属性值获取元素的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！