T
ARGETING
W
INDOWS
This feature gives the document writer a little control over where the
data appears when a user clicks on a link in their document. It is useful as
a stand alone feature with a document space that can be best viewed with
multiple top level windows (a list of subjects window, and a window
displaying the current subject), but it is most useful in conjunction with
Netscape's new
frames feature.
How it works
Previously when a user clicked on a link, the new document either
appeared in the window the user had clicked in, or alternately (and under
the user's control) it appeared in a new window. Targeting windows allows
the document writer to assign names to specific windows, and target certain
documents to always appear in the window bearing the matching name.
A name is assigned to a window in one of three ways:
- A document can be sent with the optional HTTP header
Window-target:
window_name
This will force the document to load in the window named
window_name, or if such a window does not exist, one will be created,
and then the document will be loaded in it.
- A document can be accessed via a targeted link. In this case there is
actual HTML which assigns a target
window_name to a link. The document loaded from that link will behave
as if it had a
Window-target set as in method 1 above.
- A window created within a frameset can be named using the
NAME attribute to the
FRAME tag. (
see frames)
How the HTML looks
Targeting withing HTML is accomplished by means of the
TARGET attribute. This attribute can be added to a variety of HTML
tags to target the links referred to by that tag. The attribute is of the
form:
TARGET="
window_name
"
-
TARGET in an
A tag.
- This is very straightforward. The anchor tag normally specifies a link
to be loaded when the active item is clicked on, adding the
TARGET attribute to the anchor tag forces the load of that link
into the targeted window. Example:
<A HREF="
url
" TARGET="
window_name
">Targeted Anchor</A>
-
TARGET in the
BASE tag.
- This is used when you want all (or most) of the links in a document to
be targeted to the same window. In this case the
TARGET attribute establishes a default
window_name that all links in this document will be targeted to. This
default is of course overridden by specific instances of the
TARGET attribute in individual anchor tags. Example:
<BASE TARGET="
window_name
">
-
TARGET in the
AREA tag.
- The
IETF Internet-Draft of Client-Side Image Maps defines an area
tag. This tag describes a shaped area in a client-side image map, and
provides the link that should be followed when the user clicks there. Adding
the
TARGET attribute to the area tag forces the load of that link into
the targeted window. Example:
<AREA SHAPE="
shape
" COORDS="
x,y,...
" HREF="
url
" TARGET="
window_name
">
-
TARGET in the
FORM tag.
- The form tag normally displays the results of a form submission in the
same window the form was submitted from. By adding the
TARGET attribute to the form tag, the result of the form submission
is instead loaded into the targeted window. Example:
<FORM ACTION="
url
" TARGET="
window_name
">
Allowed TARGET names
The window name specified by a
TARGET attribute must begin with an alpha-numeric character to be
valid. All other window names will be ignored.
Exception: There are magic target names that all begin with the
underscore character.
Magic TARGET names
These names all begin with the underscore character. Any targeted window
name beginning with underscore which is
not one of these names, will be ignored.
-
TARGET="_blank"
- This target will cause the link to always be loaded in a new blank
window. This window is not named.
-
TARGET="_self"
- This target causes the link to always load in the same window the anchor
was clicked in. This is useful for overriding a globally assigned
BASE target.
-
TARGET="_parent"
- This target makes the link load in the immediate
FRAMESET parent of this document. This defaults to acting like
"_self" if the document has no parent.
-
TARGET="_top"
- This target makes the link load in the full body of the window. This
defaults to acting like
"_self" if the document is already at the top. It is useful for
breaking out of an arbitrarily deep
FRAME nesting.
For a description of the
FRAMESET and
FRAME tags,
see frames.