Question

So you have a third-party web service that likes to abuse XML and return things in an order that makes your programming a complete pain in the neck. For example…

<file>   <node1>Foo</node1>   <price>4.99</price>   <node2>     <key>XX999</key>   </node2> </file> 

There are about a thousand of these sorted in order by price.

How can you re-sort this XML document by the key value?

I need the result to be a sorted XML file. Thanks!

EDIT: .NET version 2.0 (no LINQ)

Answer 1

Here’s how to do it with XSLT:

assuming your data takes this form (file.xml):

<?xml version='1.0'?> <listing> <file>   <node1>Foo</node1>   <price>4.99</price>   <node2>     <key>XX999</key>   </node2> </file> <file>   <node1>Bar</node1>   <price>5.67</price>   <node2>     <key>aa743</key>   </node2> </file> <file>   <node1>Was</node1>   <price>5.67</price>   <node2>     <key>rr321</key>   </node2> </file> </listing> 

This transform (stylesheet.xsl):

<xsl:stylesheet version='1.0' xmlns:xsl='http://www.w3.org/1999/XSL/Transform'>   <xsl:strip-space elements='*'/>   <xsl:output method='xml' indent='yes'/>    <xsl:template match='listing'>     <xsl:copy>       <xsl:apply-templates select='file'>         <xsl:sort select='node2/key' data-type='text'/>       </xsl:apply-templates>     </xsl:copy>   </xsl:template>    <xsl:template match='@* | node()'>     <xsl:copy>       <xsl:apply-templates select='@* | node()'/>     </xsl:copy>   </xsl:template>  </xsl:stylesheet> 

When used with this .Net code (need to add a using System.Xml;):

XslCompiledTransform xslt= new XslCompiledTransform(); xslt.Load(@'c:\stylesheet.xsl');  xslt.Transform(@'C:\file.xml', @'c:\sorted.xml'); 

Results in this output in sorted.xml:

<?xml version='1.0' encoding='utf-8'?> <listing>   <file>     <node1>Bar</node1>     <price>5.67</price>     <node2>       <key>aa743</key>     </node2>   </file>   <file>     <node1>Was</node1>     <price>5.67</price>     <node2>       <key>rr321</key>     </node2>   </file>   <file>     <node1>Foo</node1>     <price>4.99</price>     <node2>       <key>XX999</key>     </node2>   </file> </listing>