PCDATA and RCDATA - what is the difference?

[rc]

Please someone explain the difference between PCDATA and RCDATA. Thanks a lot.

[zcorpan]

In HTML, elements that are "PCDATA" are parsed as "normal" HTML -- that is, < and & are markup-significant charaters that start tags and entities, respectively. "RCDATA" elements are parsed as text with entities -- "<" does not start a tag (unless it's part of the element's end tag), and so RCDATA elements can't have element childen.

Example:

Code: Select all

<div><b>PCDATA</b></div>

<textarea><b>RCDATA</b></textarea>

(Notice how the text in the textarea becomes "<b>RCDATA</b>" instead of just "RCDATA".)

HTH

[rc]

Thank you. But then what is the difference between RCDATA and CDATA?

[zcorpan]

CDATA can't have entities -- just text. e.g. "&auml;" is replaced with "ä" in PCDATA and (unless it's in an "escaped text span") in RCDATA, but is literally the characters "&auml;" in CDATA (and in RCDATA when it's in an "escaped text span").

Code: Select all

PCDATA:
<div>&auml;</div>

RCDATA:
<textarea>&auml;</textarea>

RCDATA with escaped text span:
<textarea><!--&auml;--></textarea>

CDATA:
<style> /* &auml; */ head, style { display:block } </style>

[rc]

Thanks again. And one more question: what means "R" in "RCDATA"?

[zcorpan]

Replaced.