XSLT: How Do We Use It?

Nancy HallbergNikki Massaro Kauffman

XSLT: Agenda

• Introduction & Terminology• XSLT Walkthrough • Client-Side XSLT/XHTML• Server-Side XSLT/XHTML• More Creative Server-Side XSLT…

XSLT: Terminology

• CSS• HTML v. XHTML• XML• XPath• XSL• XSLT

XSLT: Alphabet Soup

• CSS & HTML• XML - Extensible Markup Language• XSL - Extensible Stylesheet Language• XHTML

XSLT: XPath

• XPath is a language for finding information in an XML document.

• XPath is used to navigate through elements and attributes in an XML document.

• Location paths can be Relative or Absolute.

XSLT: XPath

• Parents• Children• Ancestors• Descendents• Siblings• Attributes

XSLT: XPath

• Expanded Syntax /child::contacts/child::contact/child::lastname

• Abbreviated Syntax /contacts/contact/lastname

XPath Abbreviated Syntax

/ // . .. @ * [ ]

XSLT: Xpath Examples

What do the following indicate?• /• iddCourseModel/courseTitleShort• courseContent/lesson/page• ../lesson[@directory != ‘lessonshare’]• /contacts//phone

XSLT: What is XSLT?

• Extensible Stylesheet Language Transformation

• Transforms XML documents into other documents Another XML doc HTML doc PDF file And more….

XSLT: How Do We Use XSLT?

• Often used as client-side to cache formatting so only data is downloaded.

• Can transform into PDF, EDI, or other formats.

• We use it for XHTML page navigation, CSS, DWT, .htaccess, and more…

Data XHTML

XSLXML

XSLT: Template Elements

• apply-templates• call-template• choose / when /

otherwise• comment• for-each• if• import• include

• key • output• param• sort • stylesheet• template• value-of• variable

XSLT: <xsl:stylesheet>

• Defines the root element of a stylesheet.

<xsl:stylesheet> or <xsl:transform>

XSLT: <xsl:output>

• Defines the format of the output document.

• It must be a top-level element.• Method attributes are xml, html, text

<xsl:output method="html” encoding="ISO-8859-1"/>

XSLT: <xsl:template>

• An XSLT stylesheet consists of one or more set of rules that are called templates.

• Each template contains rules to apply when a specified node is matched.

• The value of the match attribute is an XPath expression.

<xsl:template match="/">

XSLT: <xsl:text>

• Exactly what it sounds like - writes text to the output.

• Attribute of disable-output-escaping

<xsl:text disable-output-escaping="yes"><![CDATA[<a name="top" id="top"></a>]]></xsl:text>

XSLT: <xsl:variable>

• Declares a variable• The variable is global if it's declared as a

top-level element, and local if it's declared within a template.

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

<xsl:variable name="titleofpage">Course Syllabus</xsl:variable>

XSLT: <xsl:value-of>

• Extracts the value of an XML element and adds it to the output stream of the transformation.

• The value of the select attribute is an XPath expression.

<xsl:value-of select="iddCourseModel/CourseTitleLong” />

XSLT: <xsl:if>

• Yea! Conditionals.• Test is a required attribute. It contains

the expression to be evaluated.

<xsl:if test="iddCourseModel/gencourPhil"></xsl:if>

<xsl:if test="mi != ''"></xsl:if>

XSLT: <xsl:for-each>

• Selects every element in a specified node set.

<xsl:for-each select="iddCourseModel/gencourPhil">

XSLT: <xsl:sort>

• Sorts the output• The select attribute indicates what

XML element to sort on.

<xsl:sort select="@orderNumber" data-type="number" order ="ascending"/>

XSLT: <xsl:choose>• Multiple conditionals• Instead of If – Then – Else or switch case• Choose – When - Otherwise<xsl:choose> <xsl:when test="objectiveStem"> <p><xsl:value-of select="objectiveStem” /></p> </xsl:when> <xsl:otherwise> <p>Upon completion of this course you will:</p> </xsl:otherwise></xsl:choose>

XSLT: <xsl:apply-templates>

• The <xsl:apply-templates> element applies a template to the current element or to the current element's child nodes.

• Adding a select attribute to the <xsl:apply-templates> element makes it process only the child element that matches the value of the attribute.

• Using the select attribute can also specify the order in which the child nodes are processed.

XSLT: <xsl:call-template>

• Templates can be called by name.• Calls can be recursive.• Be careful of the difference between

apply-templates & call-template.

XSLT: <xsl:param>

• Declares a parameter• The parameter is global if it's declared as

a top-level element, and local if it's declared within a template.

• To pass a parameter to it from another template, use <xsl:with-param>.<xsl:param name="theme"/><xsl:with-param name="theme"><xsl:value-of

select="$theme"/></xsl:with-param>

XSLT: <xsl:import>

• Imports the contents of one style sheet into another.

• An imported style sheet has lower precedence than the importing style sheet.

• This element must appear as the first child node of <xsl:stylesheet> or <xsl:transform>.

XSLT: <xsl:include>

• The <xsl:include> element is a top-level element that includes the contents of one style sheet into another.

• An included stylesheet has the same precedence as the including style sheet.

• This element must appear as a child node of <xsl:stylesheet> or <xsl:transform>.

XSLT: <xsl:key>

• a top-level element which declares a named key that can be used in the style sheet with the key() function.

<xsl:key name="themes" match="theme" use="@name"/>

<xsl:for-each select="key('themes', $theme)"><xsl:variable name="dark"><xsl:value-of select="@dark"/></xsl:variable></xsl:for-each>

XSLT: Help

Feel free to contact us with questions:

Nancy Hallberg, ndw1@psu.edu

Nikki Massaro Kauffman, lnm105@psu.edu

Additional resources are available at http://www.personal.psu.edu/lnm105