ID names within a <div></div> pair?

[Mark]

Dear folks,

In Javascript, is it possible to get all id names within, say, a
<div></divpair? Like the array of "document.image s", I mean.

The reason I ask, is that I have a calender whose <td></tdtable
elements, within a given <div></div>, all have a class type, one of which
is "today" (to highlight it). Once the calender is drawn, the Javascript
has ended. And since Javascript has no known (to me) method of storing
variables in say, the system environment, on re-use I'll have to resort to
canceling the classes for all ids within the calender before I can
highlight a different day.

Make sense? :)

Thanks,

- Mark

[Dr J R Stockton]

In comp.lang.javas cript message <es*********@ne ws1.newsguy.com >, Tue, 27
Feb 2007 18:58:46, Matt Kruse <ne********@mat tkruse.composte d:

>In validating, there's no need to check for Leapness until it has been
established that it is a Feb 29 date. But for shorter code one can
compare the date with 28+Leap(Y) .

Code was written years ago and never optimized. Although premature
optimization is unnecessary, the code could certainly stand to be less
verbose in places. A full re-write is on my to do list, and has been for
almost 2 years.

That means that it will not be done.

Here's a start :
if (!Date.prototyp e.getFullYear) {
Date.prototype. getFullYear = function() { var yy=this.getYear ();
return (yy<1900?yy+190 0:yy); }

I've heard of a browser, I think, for which getYear() would currently
return 7. My site has a function getFY which is not much longer and
uses in effect only getYear()%100.

function getFY(D) { var YE // needs full test in all browsers
YE = 1970 + Math.round(D.ge tTime() / 31556952000) // s per Greg yr
return YE + (D.getYear()-YE)%100 }

Note : it is not sensitive to errors on the values of 1970 and
31556952000, since YE only determines the century.

this.isInteger = function(val) {
for (var i=0; i < val.length; i++) {
if ("1234567890".i ndexOf(val.char At(i))==-1) {
return false;
}
}
return true;
};

can probably be

this.isInteger = function(val) ( return ! /\D/.test(val) }

if (interval=='y') { // year
this.setFullYea r(this.getFullY ear()+number);
}
else if (interval=='M') { // Month
this.setMonth(t his.getMonth()+ number);
}

Needs consideration of values that would land on a day that the
destination month does not have. Generally, use the last day of the
month; sometimes, the first of the next month. Wikipedia refers to a
case where a date/time in Feb 29 rounds down before noon and up from
noon.

Stepping weekdays can be optimised for speed by extracting multiples of
5 days and adding 7 days for each. If that is done with an appropriate
version of mod & div, the fractional-week count need only be forwards,
which may be simpler.

>In <http://www.javascriptt oolbox.com/lib/date/examples.php>, the
"Adding Time" demo must have a problem. If I add 7500000 seconds and
0..7 years to 2000-01-01 01:00:00, I should not always get the same
time of day.

Interesting. Have you looked at the code and found where the bug might be? I
have not yet verified myself that there is a bug, but if you have a patch it
would be great.

Apart from your determination of the current year, probably everything
else can be done in Greenwich Time. It is especially obvious, as 3/11
approaches, what problem that annihilates. The UTC methods should be
several times faster; and in at least one case (same date) are not
needed at least for post-1969. (check that)

Math.floor(D1/864e5) == Math.floor(D2/864e5)

--
(c) John Stockton, Surrey, UK. ?@merlyn.demon. co.uk Turnpike v6.05 IE 6.
Web <URL:http://www.merlyn.demo n.co.uk/- w. FAQish topics, links, acronyms
PAS EXE etc : <URL:http://www.merlyn.demo n.co.uk/programs/- see 00index.htm
Dates - miscdate.htm moredate.htm js-dates.htm pas-time.htm critdate.htm etc.

[Matt Kruse]

Dr J R Stockton wrote:

>A full re-write is on my to do list, and has
been for almost 2 years.

That means that it will not be done.

What else can you tell me about my future, all-seeing one?!

--
Matt Kruse
http://www.JavascriptToolbox.com
http://www.AjaxToolbox.com

[Dr J R Stockton]

In comp.lang.javas cript message <es*********@ne ws5.newsguy.com >, Fri, 2
Mar 2007 22:22:43, Matt Kruse <ne********@mat tkruse.composte d:

>Dr J R Stockton wrote:

>>A full re-write is on my to do list, and has
been for almost 2 years.

That means that it will not be done.

What else can you tell me about my future, all-seeing one?!

Well, it would be non-constructive to say that you'll be so determined
to prove me wrong that you'll fully rewrite it within the next week, so
I won't.

For conversion from 24-hr H to 12-hr h, consider h = 1 + (H+11)%12
as per IIRC via the FAQ.

ISTM that isBlank should recognise \u00A0 and maybe others.

Does parseFloat really use a second parameter? parseFloat(val) >= 0
should do except for the case of "-0" (see its comment); but I don't see
that yours tests for positive.

The knowledge base search seems good at first on "Date Validation" and
"Lagrange Point", but I learned little from its results :-( .

A further prediction is that if you go for a policy of incremental
improvement, utility and uptake will increase more rapidly than
otherwise. In particular, the absence of RegExps in parts of the code
makes it look very dated. They're in small Flanagan of Oct 1998.

--
(c) John Stockton, Surrey, UK. ?@merlyn.demon. co.uk Turnpike v6.05 MIME.
Web <URL:http://www.merlyn.demo n.co.uk/- FAQqish topics, acronyms & links;
Astro stuff via astron-1.htm, gravity0.htm ; quotings.htm, pascal.htm, etc.
No Encoding. Quotes before replies. Snip well. Write clearly. Don't Mail News.

[Matt Kruse]

Dr J R Stockton wrote:

>What else can you tell me about my future, all-seeing one?!

Well, it would be non-constructive to say that you'll be so determined
to prove me wrong that you'll fully rewrite it within the next week,
so I won't.

Rest assured, your sphere influence is far greater in your mind than in
reality ;)

I'm currently working on completing my table-handling script, which handles
sorting, filtering, paging, and aggregating. It's quite a challenging and
interesting script to work on, with considerable practical applications to
my current work. The calendar popup, not so much.

A further prediction is that if you go for a policy of incremental
improvement, utility and uptake will increase more rapidly than
otherwise. In particular, the absence of RegExps in parts of the code
makes it look very dated. They're in small Flanagan of Oct 1998.

I wrote that code back when I needed to support a browser without regular
expressions, and when I converted it to its new form I wasn't interested in
re-writing working logic. Now, such browsers are probably non-existent in
the real world, and the code I write now makes use of regular expressions
whenever necessary.

--
Matt Kruse
http://www.JavascriptToolbox.com
http://www.AjaxToolbox.com