XML DOES NOT USE predefined tags and the meanings of these tags are not well understood.
The <table> could mean an HTML table or a piece of furniture. Abrowser does not know
how to display it.
There must be something in addition to the XML document that describes how the
document should be displayed; and that is XSL!


XSLT - XSL TRANSFORMATIONS
XSLT is the most important part of the XSL Standards. It is the part of XSL that is used to
transform an XML document into another XML document, or another type of document that is
recognized by a browser, like HTML and XHTML.

Normally XSLT does this by transforming each XML element into an (X)HTML element.

XSLT can also add new elements into the output file, or remove elements. It can rearrange
and sort elements, and test and make decisions about which elements to display,
and a lot more.

A common way to describe the transformation process is to say that XSLT
transforms an XML source tree into an XML result tree.

How does it Work?
In the transformation process, XSLT uses XPath to define parts of the source document that
match one or more predefined templates. When a match is found, XSLT will transform the matching
part of the source document into the result document. The parts of the source document that do
not match a template will end up unmodified in the result document


! <xsl:stylesheet> and <xsl:transform> are completely synonymous and either can be used!


<xsl:transform version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

1 We want to transform the following XML document ("cdcatalog.xml") into XHTML:


2 Create an XSL Style Sheet
  Then you create an XSL Style Sheet ("cdcatalog.xsl") with a transformation template:

3 Link the XSL Style Sheet to the XML Document
  Finally, add an XSL Style Sheet reference to your XML document ("cdcatalog-transformed.xml"):


 An XSL style sheet consists of a set of rules called templates.
 Each <xsl:template> element contains rules to apply when a specified node is matched.

  <td><xsl:value-of select="catalog/cd/title"/></td>
  The value of the required select attribute contains an XPath expression.


  BASICS

  Loop through all titles:

  <xsl:for-each select="catalog/cd">
        <tr>
          <td><xsl:value-of select="title"/></td>
          <td><xsl:value-of select="artist"/></td>
        </tr>
   </xsl:for-each>

 Example filter:
  <xsl:for-each select="catalog/cd[artist='Bob Dylan']">


 Example SORT:
	...
	<xsl:for-each select="catalog/cd">
	<xsl:sort select="artist"/>
		<tr>
			<td><xsl:value-of select="title"/></td>
			<td><xsl:value-of select="artist"/></td>
		</tr>
	</xsl:for-each>



Example IF:
	<xsl:for-each select="catalog/cd">
	<xsl:if test="price Ampgt; 10">
		<tr>
			<td><xsl:value-of select="title"/></td>
			<td><xsl:value-of select="artist"/></td>
		</tr>
	</xsl:if>
	</xsl:for-each>


Example CHOOSE:
	<xsl:choose> element is used in conjunction with
	<xsl:when> and <xsl:otherwise> to express multiple conditional tests.

	<xsl:for-each select="catalog/cd"<
		<tr>
			<td><xsl:value-of select="title"/></td>
			<xsl:choose>
			<xsl:when test="price > 10">
			<td bgcolor="#ff00ff">
			<xsl:value-of select="artist"/></td>
			</xsl:when>
			<xsl:otherwise>
			<td><xsl:value-of select="artist"/></td>
		</xsl:otherwise>
		</xsl:choose>
		</tr>
	</xsl:for-each>

XSLT Elements Reference

The XSLT elements from the W3C Recommendation (XSLT Version 1.0).

XSLT Elements

The links in the "Element" columns point to attributes and more useful information about the specific element.

• NN: indicates the earliest version of Netscape that supports the tag
• IE: indicates the earliest version of Internet Explorer that supports the tag

Note: All elements supported in IE 5.X may have NON-standard behavior, because IE 5.X was released before XSLT became a W3C Recommendation!