XML CDATA vs PCDATA

CDATA (Character Data) and PCDATA (Parsed Character Data) are used to represent different types of character data within an XML document.

Syntax

• CDATA stands for Character Data.
• It allows the creation of blocks of unstructured data within an XML document.
• The syntax for CDATA is as follows:

<![CDATA[
    ... Unstructured Data ...
]]>

PCDATA stands for Parsed Character Data. It allows the creation of structured data within an XML document. The syntax for PCDATA is as follows:

<element> Structured Data </element>

Example

CDATA

<description>
    <![CDATA[
        This is a block of unstructured data.
        And it may contain any special characters, like "<", ">", "/", "'", "&",  etc.
    ]]>
</description>

PCDATA

<book>
    <title> Understanding PCDATA and CDATA </title>
    <author> John Doe </author>
    <description>
        This book is a guide to understand PCDATA and CDATA. You will learn how to use these two formats to structure your data in XML.
    </description>
    <price> 29.99 </price>
</book>

Output

CDATA

The output of the CDATA example would be:

<description>
    This is a block of unstructured data.
    And it may contain any special characters, like "<", ">", "/", "'", "&",  etc.
</description>

PCDATA

The output of the PCDATA example would be:

<book>
    <title> Understanding PCDATA and CDATA </title>
    <author> John Doe </author>
    <description>
        This book is a guide to understand PCDATA and CDATA. You will learn how to use these two formats to structure your data in XML.
    </description>
    <price> 29.99 </price>
</book>

Explanation

CDATA is used to include blocks of unstructured data, such as HTML code, within an XML document. The contents of a CDATA section are ignored by the parser and do not need to be well-formed XML.

PCDATA, on the other hand, is used to include structured data within an XML document. The contents of a PCDATA element are parsed by the parser and must be well-formed XML.

Use

CDATA is commonly used to include special characters, such as quotes, within an XML document without having to escape them. It is also useful for including chunks of HTML within an XML document.

PCDATA is used to structure the content of an XML document and should be used for all structured data.

Important Points

• CDATA is used for unstructured data, while PCDATA is used for structured data.
• CDATA sections are ignored by the parser, while PCDATA elements are parsed.
• CDATA is commonly used for HTML code and special characters.
• PCDATA should be used for all structured data and must be well-formed XML.

Summary

In summary, CDATA and PCDATA are two formats used for including data within an XML document. CDATA is used for unstructured data, such as HTML code, while PCDATA is used for structured data within an XML document. CDATA sections are ignored by the parser, while PCDATA elements are parsed by the parser and must be well-formed XML.