XSL Transformation Instructions

• XSL's most powerful feature

• Typical transformations:
  • Extract only the data we want
  • Sort it
  • Add new information

• Some transformation instructions:

  xsl:apply-templates	Applies a template to data that matches a pattern (example seen previously). <xsl:template match="author"> <LI> <xsl:apply-templates select="last"/>, <xsl:apply-templates select="first"/>. </LI> </xsl:template> The example lists last name, a comma, first name, and a period, as an HTML bullet list.
  xsl:text	Outputs the raw text within the element, including white space. (This was discussed in an earlier lab.)
  @	Attributes are specified with @. For example: chapter/@optional matches the attribute named optional belonging to an element named chapter.
  xsl:value-of	Matches a pattern in the select attribute and generates an element in the result tree containing the matched text. (If you need to generate an attribute instead of an element, use {}, discussed below.) Example: <xsl:value-of select="@language" />
  Lab 4C
  xsl:choose	XSL's "switch" statement. It works together with the xsl:when and xsl:otherwise instructions. Example: <xsl:choose> <xsl:when test="@required='NO'"> (Optional) </xsl:when> <xsl:when test="@required='YES'"> (Required) </xsl:when> <xsl:otherwise> (Unknown) </xsl:otherwise> </xsl:choose>
  xsl:if	Branching logic (if-then). For example: <xsl:if test="@required='NO'"> (Optional) </xsl:if> outputs "(Optional)" if the required attribute is "NO".
  Lab 4D