Cdata Sections

Xml

CDATA Sections are used to escape a whole block of text.

The XML processor knows to escape all data between the CDATA tags.

You declare a CDATA section using <![CDATA[ as the opening tag, and ]]> as the closing tag.

Compare with entity reference, escaping a single character.

Syntax:

<root>
  <child>
  <![CDATA[
    Text you want to escape goes here...
  ]]>
  </child>
</root>

Cdata in Program output:

Since it is useful to be able to use less-than signs (<) and ampersands (&) in web page scripts, and to a lesser extent styles, without having to remember to escape them, it is common to use CDATA markers around the text of inline <script> and <style> elements in XHTML documents. But so that the document can also be parsed by HTML parsers, which do not recognise the CDATA markers, the CDATA markers are usually commented-out.

Eg: cdata in script output. CDATA markers are usually commented-out in js.

    
<script type="text/javascript">
    // <![CDATA[

        function printAlert {
            alert("hello world!");
        }

    // ]]> 
</script>

Eg2: in css. Here too, cdata markers are commented out.

<style type="text/css">
    /*<![CDATA[*/

        body { background-image: url("marble.png?width=300&height=300") }     
  
    /*]]>*/
</style>