XML xsl:choose
The xsl:choose
element in XML is used for conditional processing within XSLT stylesheets.
Syntax
<xsl:choose>
<xsl:when test="condition">
<!-- Actions to perform when the condition is true -->
</xsl:when>
<xsl:otherwise>
<!-- Actions to perform when the condition is false -->
</xsl:otherwise>
</xsl:choose>
Example
Consider a simple XML transformation using xsl:choose
:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:template match="/">
<html>
<body>
<xsl:choose>
<xsl:when test="condition">
<!-- Output when condition is true -->
</xsl:when>
<xsl:otherwise>
<!-- Output when condition is false -->
</xsl:otherwise>
</xsl:choose>
</body>
</html>
</xsl:template>
</xsl:stylesheet>
Output
The output of the transformation will vary based on the conditions specified in the xsl:choose
block.
Explanation
The xsl:choose
element allows for multiple conditional checks (xsl:when
) within an XSLT stylesheet. It evaluates each condition sequentially and executes the block associated with the first true condition. If no condition is true, it executes the xsl:otherwise
block.
Use
- Use
xsl:choose
when you need to apply different transformations or actions based on different conditions in your XML document. - It's beneficial when you want to handle various cases or scenarios while transforming XML data.
Important Points
xsl:choose
must contain at least onexsl:when
.- Multiple
xsl:when
blocks can be used within a singlexsl:choose
. - The
xsl:otherwise
block is optional but serves as a default action when no conditions are met.
Summary
The xsl:choose
element in XML is instrumental for conditional processing in XSLT. It allows for the execution of different actions based on specified conditions, providing a way to handle diverse scenarios while transforming XML data.