Can I return a whole XML document using XPath in javascript?

I am using Javascript, and I want to return an XML document with the results I want.

For example, the XML document can be <books> <book> <title> Introduction to XML </title> </book> <book> <title> Introduction to Javascript </title> </book> </books>

and using this XPath expression: //book[./title="Introduction to XML"] I want to get a document like that <boo开发者_运维问答ks> <book> <title> Introduction to XML </title> </book> </books>

I know XQuery sounds like the solution here, but I am using Javascript, and there are no built-in implementations, as far as I know, for XQuery in Javascript.

I want to return the ancestors along with the thing I need. But it should also work if I get several results.. is this doable using XPath?

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XPath cannot change the source XML document and cannot produce a new XML document.

Therefore, some other technology has to be used for this. XSLT is a language especially designed for wxpressing such transformations.

In most browsers you can process an XML document with an XSLT stylesheet identified by an associating <?xml-stylesheet ?> PI (processong instruction).

Most browsers also offer some way of initiating an XSLT transformation in Javascript -- read your browser documentation.

The XSLT transformation itself is very simple:

<xsl:stylesheet version="1.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output omit-xml-declaration="yes" indent="yes"/>
 <xsl:strip-space elements="*"/>

 <xsl:param name="pTitleWanted" select="' Introduction to XML '"/>

 <xsl:template match="node()|@*" name="identity">
     <xsl:copy>
       <xsl:apply-templates select="node()|@*"/>
     </xsl:copy>
 </xsl:template>

 <xsl:template match="books">
  <xsl:copy>
    <xsl:apply-templates select="book[title = $pTitleWanted]"/>
  </xsl:copy>
 </xsl:template>
</xsl:stylesheet>

when this transformation is applied to the provided XML document:

<books>
    <book>
        <title> Introduction to XML </title>
    </book>
    <book>
        <title> Introduction to Javascript </title>
    </book>
</books>

the wanted, correct result is produced:

<books>
   <book>
      <title> Introduction to XML </title>
   </book>
</books>

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Browser JavaScript Environment comes with default Xml Document Object Model Parser.

You can take advantage of that control and parse it as Dom Parsing Style.

enter code here
var _xml = "<books> <book> <title> Introduction to XML </title> </book> </books>"
parser=new DOMParser();
xmlDoc=parser.parseFromString(_xml,"text/xml");
//Use any type of DOM API to parse
xmlDoc.childNodes()...... 

This code is for FireFox Browser. You can do the same thing in IE using their ActiveXControls as like XmlHttp way.

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In general, no you can't do that with XPath on its own - it's only an expression language. XPath cannot create nodes it can only select them. You can (as you have) select a set of nodes but you can't then wrap them up in other nodes.

You certainly could vary @kadalmittai's suggestion and use the DOM API to select your nodes, create a new document and clone your selected nodes into it but that is fairly heavyweight given your fairly simple requirement.

XSLT might be a better approach here but I don't know enough about browser technologies to tell you how to use it in the browser.