position Function

Returns the position, or index number, of the node, relative to all the selected nodes in the node list.

      number position()


The position of the node is is 1-based, so the first node returns a position of 1.


The following code example illustrates the effects of the position() function.

XML File (position.xml)

<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="position.xsl"?>      
    <x a="a11">
      <x a="a21">
        <x a="a31">
          <y b="b31">y31</y>
          <y b="b32">y32</y>
    <x a="a12">
      <x a="a22">
        <y b="b21">y21</y>
        <y b="b22">y22</y>
    <x a="a13">
      <y b="b11">y11</y>
      <y b="b12">y12</y>
    <x a="a14">
      <y b="b01">y01</y>
      <y b="b02">y02</y>

XSLT File (position.xsl)

<?xml version='1.0'?>

  <xsl:output method="xml"   

  <xsl:template match="/">
     <xsl:apply-templates select="//x"/>

  <xsl:template match="*">
    <xsl:element name="{name()}">
        <xsl:apply-templates select="@*"/>
        <xsl:value-of select="position()"/>

  <xsl:template match="@*">
     <xsl:attribute name="{name()}">
        <xsl:value-of select="."/>



The above XSLT style sheet, when applied to the source XML file, maps all the <x> elements to new <x> elements whose content holds their position in the document order.

<x a="a11">1</x>
<x a="a21">2</x>
<x a="a31">3</x>
<x a="a12">4</x>
<x a="a22">5</x>
<x a="a13">6</x>
<x a="a14">7</x>

To illustrate the sensitivity of the position() function to the context from which it is operated, let's replace the following template rule (from the XSLT file above):

<xsl:template match="/">
  <xsl:apply-templates select="//x"/>

with this one:

<xsl:template match="/">
     <xsl:apply-templates select="//x[1]"/>

The result is as follows:

<x a="a11">1</x>
<x a="a21">2</x>
<x a="a31">3</x>
<x a="a22">4</x>

On the other hand, if we replace the template rule with the following one:

<xsl:template match="/">
  <xsl:apply-templates select="//x[2]"/>

we get the following result:

<x a="a12">1</x>                 

See Also


XML Data Types Reference