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XSLT <xsl:variable> Element

Complete XSLT Element Reference

Definition and Usage

The <xsl:variable> element is used to declare a local or global variable.

Note: The variable is global if it's declared as a top-level element, and local if it's declared within a template.

Note: Once you have set a variable's value, you cannot change or modify that value!

Tip: You can add a value to a variable by the content of the <xsl:variable> element OR by the select attribute!

Syntax

<xsl:variable
name="name"
select="expression">

  <!-- Content:template -->

</xsl:variable>

Attributes

Attribute	Value	Description
name	name	Required. Specifies the name of the variable
select	expression	Optional. Defines the value of the variable

Example 1

If the select attribute is present, the <xsl:variable> element cannot contain any content. If the select attribute contains a literal string, the string must be within quotes. The following two examples assign the value "red" to the variable "color":

<xsl:variable name="color" select="'red'" />

<xsl:variable name="color" select='"red"' />

Example 2

If the <xsl:variable> element only contains a name attribute, and there is no content, then the value of the variable is an empty string:

<xsl:variable name="j" />

Example 3

The following example adds a value to the variable "header" by the content of the <xsl:variable> element:

<?xml version="1.0" encoding="ISO-8859-1"?>
<xsl:stylesheet version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

<xsl:variable name="header">
  <tr>
  <th>Element</th>
  <th>Description</th>
  </tr>
</xsl:variable>

<xsl:template match="/">
  <html>
  <body>
  <table>
    <xsl:copy-of select="$header" />
    <xsl:for-each select="reference/record">
    <tr>
    <xsl:if category="XML">
      <td><xsl:value-of select="element"/></td>
      <td><xsl:value-of select="description"/></td>
    </xsl:if>
    </tr>
    </xsl:for-each>
  </table>
  <br />
  <table>
    <xsl:copy-of select="$header" />
    <xsl:for-each select="table/record">
    <tr>
    <xsl:if category="XSL">
      <td><xsl:value-of select="element"/></td>
      <td><xsl:value-of select="description"/></td>
    </xsl:if>
    </tr>
    </xsl:for-each>
  </table>
  </body>
  </html>
</xsl:template>

</xsl:stylesheet>

Complete XSLT Element Reference