The DEL element is one of two elements used (the other being
INS) to allow revision control in
HTML documents. The DEL element is nestable and can be used in
conjunction with the INS element to indicate content and/or markup
which has been deleted after the document's initial creation - it
is not really eliminated from the document though. A date stamp
is used to mark when the change was made and no destructive changes
are ever made to the document. This is useful in areas such as the
legal profession where historical change information is important.
HTML documents containing revision annotations will contain all
content and markup ever applied to the document. Browsers that
can interpret the DEL and INS elements could possibly display the
"current" state of the document or display all content with
common visual cues for inserted or deleted text. More advanced revision
systems could allow for chronological snapshots of a document at any
point in its history.
Description:
Indicates the date and time when the contents were deleted.
Values: CDATA. ISO Date format:
[YYYY-MM-DDThh:mm:ssTZD where:
YYYY = Four-digit year
MM = Two digit month (01-12)
DD = Two digit day of month (01-31)
hh = Two digit hour (00-23, no AM/PM designation is used)
mm = Two digit minutes (00-59)
ss = Two digit seconds (00-59)
TZD = Time zone designator]
Compatibility Tip: Older browsers that
do not understand the INS and DEL elements will display all revision
content on-screen without regard to their revision state, even the
"deleted" content. This could be messy. Recommend using this
element only if you can reasonably guarantee that everyone in your audience
has a browser supporting these elements.
DTD Note: The current HTML 4.0 DTD lists INS/DEL
as content only of the BODY element. In light of its potential use,
this seems fairly limiting. I believe these elements should be
usable at least as block level elements (such as BLOCKQUOTE.)
Browser Peculiarities
IE, Mozilla/NS and Opera display deleted content with a strike-through line
through the content (as if someone applied S or STRIKE to the same content.)
Internet Explorer 4+ and Opera 4+ do not expose the CITE or DATETIME attributes
to the reader.
IE, Mozilla/NS and Opera do not offer by default any way to control views
of a document based on the state of revisions.
[Test]
INS and DEL can be nested. Because the only visual difference is strike
and underline, only simple nesting will have any visual effect. Nesting
DEL within DEL, for example, will look no different from a single DEL
element occurrence. Nesting INS within DEL however will produce the
necessary feedback.
[Test]
The CITE/DATETIME attributes are exposed in Netscape 6.1+ by invoking a
context menu on the element (PC: right clicking) and choosing "properties."