XML CDATA sections ... the good, the bad, and the ugly

["Costello, Roger L." <costello@mitre.org>]

Hi Folks,

 

The CDATA section is a mechanism for disabling the normal interpretation of XML syntax. For example, the title element in this XML document contains a script element:

 

<title>
    <script>...</script>
</title>

 

The title element in this XML document contains a string:

 

<title>
    <![CDATA[<script>...</script>]]>
</title>

 

Ordinarily <script> would be interpreted as a start tag but since <script> is embedded within a CDATA section the normal interpretation is disabled and <script> is treated simply as a string.

 

There is nothing that XSLT programs can do about CDATA sections. That is because the XML parser removes the CDATA wrapper and creates a text node for its content. The CDATA wrapper is gone by the time the XSLT program gets the XML; all that remains is a text node.

 

Nonetheless, some XSLT processors can be configured to instruct its XML parser to remove the CDATA sections. The approach for doing this varies with the XSLT processor. This article describes the approach used by one XSLT processor: http://sourceforge.net/p/saxon/mailman/message/34240016/.

 

Any errors in this description? Anything you would add or delete?

 

/Roger