Converting XML elements to XML attributes using XSLT

Question

We have a current system that outputs an XML file which is in the following format:

<INVENTORY>
   <ITEM>
      <SERIALNUMBER>something</SERIALNUMBER>
      <LOCATION>something</LOCATION>
      <BARCODE>something</BARCODE>
   </ITEM>
</INVENTORY>

I need to use this data to load into the standard .NET 2.0 grid. But the grid needs the XML to be in the following format:

<INVENTORY>
   <ITEM serialNumber="something" location="something" barcode="something">
   </ITEM>
</INVENTORY>

i.e. the child nodes of item need to be converted into attributes of the item node.

Does someone know how this can be done using XSLT?

Answer 1

This should work:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:template match="INVENTORY">
    <INVENTORY>
      <xsl:apply-templates/>
    </INVENTORY>
  </xsl:template>

  <xsl:template match="ITEM">
    <ITEM>
      <xsl:for-each select="*">
        <xsl:attribute name="{name()}">
          <xsl:value-of select="text()"/>
        </xsl:attribute>

      </xsl:for-each>
    </ITEM>
  </xsl:template>
</xsl:stylesheet>

Answer 2

Here is probably the simplest solution that will convert any children-elements of ITEM to its attributes and will reproduce everything else as is, while converting the element names to any desired attribute names:

<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:variable name="vrtfNameMapping">
    <item name="SERIALNUMBER" newName="serialNumber"/>
    <item name="LOCATION" newName="location"/>
    <item name="BARCODE" newName="barcode"/>
  </xsl:variable>
 <!--                                              --> 
  <xsl:variable name="vNameMapping" select=
  "document('')/*/xsl:variable[@name='vrtfNameMapping']"/>
<!--                                              --> 

  <xsl:template match="node()|@*">
    <xsl:copy>
      <xsl:apply-templates select="node()|@*"/>
    </xsl:copy>
  </xsl:template>
<!--                                              --> 
  <xsl:template match="ITEM/*">
    <xsl:attribute name=
     "{$vNameMapping/*[@name=name(current())]/@newName}">
      <xsl:value-of select="."/>
    </xsl:attribute>
  </xsl:template>
</xsl:stylesheet>

when the above transformation is applied on the provided XML document:

<INVENTORY>
    <ITEM>
        <SERIALNUMBER>something</SERIALNUMBER>
        <LOCATION>something</LOCATION>
        <BARCODE>something</BARCODE>
    </ITEM>
</INVENTORY>

the wanted result is produced:

<INVENTORY>
   <ITEM serialNumber="something" location="something" barcode="something"/>
</INVENTORY>

Do note the following:

1. The use of the identity rule

2. The use of <xsl:strip-space elements="*"/>

3. The use of the variable vrtfNameMapping without any xxx:node-set() extension function.

4. The fact that we handle any mapping between a name and a newName, not only simple lower-casing.