CDATA vs. PCDATA in XML: Understanding Character Data Handling

Learn the key differences between CDATA and PCDATA in XML and how to use them effectively. This tutorial explains how XML parsers handle character data, demonstrating when to use CDATA sections for including literal text and when to use PCDATA for standard text content. Master XML data handling.

CDATA vs. PCDATA in XML

In XML (Extensible Markup Language), text content within elements is categorized as either CDATA (Character Data) or PCDATA (Parsed Character Data). Understanding this distinction is important for correctly representing and interpreting text within XML documents.

CDATA Sections

CDATA sections are used to include text that should *not* be parsed by the XML parser. Any markup or entities within a CDATA section are treated as literal text, not as XML markup. This is useful for including text that might contain characters that have special meaning in XML (like `<`, `>`, `&`). CDATA sections start with `<![CDATA[` and end with `]]>`.

<employee>
  <![CDATA[
  This text contains <tags> and &entities; but they are ignored by the parser.
  ]]>
</employee>

PCDATA (Parsed Character Data)

PCDATA represents text content that *is* parsed by the XML parser. The parser interprets markup and entities within PCDATA sections. Entities (like `&`, `<`, `>`) are expanded to their corresponding characters. PCDATA is the standard way to include text content in XML elements; unless you have a specific need for treating some text literally, you should always use PCDATA.

Example: CDATA vs. PCDATA

Note: The examples below are simplified representations. To see the differences in how XML parsers handle the data, you should test these examples on a real XML parser. Screenshots from the original text are not included here. Please refer to the original document for visual verification of the example and its output. The descriptions below aim to convey the information in those screenshots.

Example 1: Basic XML Structure

This example demonstrates a simple XML document containing a single element:

<book>
  <title>XML Basics</title>
  <author>John Doe</author>
</book>
        

Output: The XML parser will correctly identify the `` element and its children, `