Question

I have an HTML file like this:

<root>
    <br>
    <h3>The first H3 text</h3><br>
    <p>para1 content in first H3</p><br>
    <p>para2 content in first H3</p><br>
    <h3>The second H3 text</h3><br>
    <p>para1 content in second H3</p><br>
    <p>para2 content in second H3</p><br>
    <p>para3 content in second H3</p><br>
    <p>para4 content in second H3</p><br>
</root>

I want to write an XSL which gives output like this one:

<sec>
    <br />
    <secHead>The first H3 text</secHead><br />
    <para>para1 content in first H3</para><br />
    <para>para2 content in first H3</para><br />
</sec>
<br />
<sec>
    <br/>
    <secHead>The second H3 text</secHead><br/>
    <para>para1 content in second H3</para><br/>
    <para>para2 content in second H3</para><br/>
    <para>para3 content in second H3</para><br/>
    <para>para4 content in second H3</para><br/>
</sec>

How can we get this output writing XSL?

Answer 1

Good question, +1.

This transformation:

<xsl:stylesheet version="1.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output omit-xml-declaration="yes" indent="yes"/>
 <xsl:strip-space elements="*"/>

 <xsl:key name="kFollowing" match="*[not(self::h3)]"
  use="generate-id(preceding-sibling::h3[1])"/>

 <xsl:template match="/*">
  <xsl:apply-templates select="h3"/>
 </xsl:template>

 <xsl:template match="h3">
    <xsl:if test="position() > 1">
     <br />
    </xsl:if>
     <sec>
      <br />
      <secHead><xsl:value-of select="."/></secHead>
      <xsl:copy-of select="key('kFollowing', generate-id())"/>
     </sec>
 </xsl:template>
</xsl:stylesheet>

when applied on the provided source (the html must be converted to wellformed XML!!!):

<root>
    <br/>
    <h3>The first H3 text</h3><br/>
    <p>para1 content in first H3</p><br/>
    <p>para2 content in first H3</p><br/>
    <h3>The second H3 text</h3><br/>
    <p>para1 content in second H3</p><br/>
    <p>para2 content in second H3</p><br/>
    <p>para3 content in second H3</p><br/>
    <p>para4 content in second H3</p><br/>
</root>

produces the wanted, correct result:

<sec>
   <br/>
   <secHead>The first H3 text</secHead>
   <br/>
   <p>para1 content in first H3</p>
   <br/>
   <p>para2 content in first H3</p>
   <br/>
</sec>
<br/>
<sec>
   <br/>
   <secHead>The second H3 text</secHead>
   <br/>
   <p>para1 content in second H3</p>
   <br/>
   <p>para2 content in second H3</p>
   <br/>
   <p>para3 content in second H3</p>
   <br/>
   <p>para4 content in second H3</p>
   <br/>
</sec>

Explanation:

The key point in this solution is that we define an xsl:key that captures the relation between an h3 element and all its immediate following siblings elements (such that they aren’t h3 themselves and this h3 is their first h3 preceding sibling).