Java Guy wrote:
RobG wrote:
JavaScript as used on the web hasn't changed since 1999 and
Microsoft's support for the core language is as good as anyones
I see references to Javascript 1.x, where x is number from 2 to 7.
When I go to this page:
http://javascript.internet.com/user-...t-version.html
I'm told:
"Your browser supports JavaScript version 1.3"
I can't comment on that code other than to say I'd distrust any such
attempt at sniffing the supported version of JavaScript. The language
attribute was deprecated when introduced, therefore it is unreasonable
to expect that browsers will reliably take any specific action based on
it. All that can be said is that any browser parsing a page as HTML 4
should tolerate its presence.
Certain values of the language attribute have known side-effects in
some older browsers, its use is strongly discouraged in favour of the
(required) type attribute.
The other followup post to my question makes a reference to "Jscript"
and specifically version 5.6.
Can someone give me an executive summary of the difference between
JavaScript and Jscript?
JScript is Microsoft's implementation of ECMAScript Language and
includes a considerable number of proprietary extensions (as do
implementations by others such as Opera, Apple and Mozilla). The
following link gives approximate equivalence between JScript and
JavaScript versions:
<URL:
http://en.wikipedia.org/wiki/Jscript >
though I can't comment on how authoritative it is.
As well as explain the consequences of having a browser that supports
version 1.3 of Javascript when (apparently) Javascript is up to
version 1.7?
The page you are basing your "1.3" number on only goes to 1.3,
therefore presuming its detection method is accurate (which it might be
for IE), it can't report anything newer.
<URL:
http://www.mozilla.org/js/language/ >
JavaScript is up to version 2.0, you can try it out if you like:
<URL:
http://www.mozilla.org/js/language/Epimetheus.html >
(I'm having problems viewing some IP or network cameras and the code
that doesn't seem to be working properly is written in Javascript -
code that came with the webcam that is)
Then you'll have to talk to the web cam vendor. ECMAScript is just a
language specification and is intended to be used as a means to
communcate with a host environment. You are dependent on the
functionality provided by that environment to actually do something
useful.
In a browser you are dependent on the DOM methods it provides to do
stuff - e.g. ECMAScript has no native or built-in mechanism for input
or output (it has no write, print, read, scan, or similar commands).
--
Rob
