[Javascript] Where to learn JS best practices & style

Michael Dougherty Michael_Dougherty at PBP.com
Fri Mar 28 17:16:21 CST 2003 

from the thread: Re: [Javascript] required entry field
(there's many off-thread ideas here, so i started a new one to possibly get
more reader's input)


No stab intended.  I spent 2 hours trying to figure out why my form.submit()
wouldn't work even though the example i was copying did.  It was because
another example i had copied used "submit" for the name of the submit
button.

are you saying that the statement "document.all.myobject.value" is more
efficiently expressed as "myobject.value"?

how about document.all["obj" + lnJ++].value?  is there another way to
reference a contruct like that?

how different is document.all.myobject.value from
myObjArray["row6"]["col5"].value?  Maybe i'm relying too much on VB/VFP's
object model where the dotted referencing is just the nomenclature for
explicitly stating the object heirarchy.  (aside from the fact that a DHTML
document doesn't really have a heirarchy)

Where does one go to learn the "right way" of writing javascript/DHTML?  I'm
not trying to be beligerant, but what source are you using to make the
statement "Scripters should avoid" anything?  Do you have quantitative
evidence that this is inefficient, or is it your opinion?  If it sounds like
i'm harping on this, it's because i DO want to write the best code (using
the best practice) possible and willingly admit that self-taught from web
examples makes me far less than an expert.  I'm also not trying to knock
anyone's advice - i just want to understand exactly how it applies.  (I have
been using document.all 'always and regularly' because i am ignorant of a
better way)  I'm wondering if there is significant impact to recode my
application....

  re: removing all the comments/short names- Are you suggesting that a
source-code be maintained with comments, and a production version without
comments?  Do you think the overhead of delivering in-line comments
outweighs the benefit of future readability/maintenance?  (consider the
target being an Intranet client with at least 10/100Mb wire-speed)  In this
same vein, do shorter (though perhaps less obvious) variable names improve
performance over more immediately readable (and somewhat "self-documenting")
variable naming conventions?  Isn't this why we've moved from 3rd to 4th
generation development languages?  By the time i've reduced my code to 3
character variable names without commenting, i might as well instantiate a
compiled object.

  I'm hoping this thread goes towards a discussion about javascript rather
than code examples of a solution.

thanks for your input in advance...

Michael_Dougherty at pbp.com

-----Original Message-----
From: javascript at LaTech.edu [mailto:javascript at LaTech.edu]
Sent: Friday, March 28, 2003 4:04 PM
To: javascript at latech.edu
Subject: Re: [Javascript] required entry field


No need for stabs, we are all exchanging experience between this
memberhood.
The question was addresed to Rodney as he sugested other way of salving
the
guy's problem.

I don't see no need to call the form collection in order to access a
single
field. Why ask browser to count items of collection once again
when you can directly and selectively retrieve its properties.

Scripters should avoid using calls like 'document.all', allways and
regularly. Give some considerations in optimizing their scripts, the speed
of execution, size of the script, removing all the comments, using short
declarations, variable names, shorter object calls and other, to achieve
faster downloads, and faster executions.

Though this prism,it's contraproductive calling collections of any kind
when
items have given Names or IDs.

Regards!



>>From: "David T. Lovering" <dlovering at gazos.com>
>>Reply-To: "[JavaScript List]" <javascript at LaTech.edu>
>>To: "[JavaScript List]" <javascript at LaTech.edu>
>>Subject: Re: [Javascript] required entry field
>>Date: Fri, 28 Mar 2003 11:15:41 -0700
>>
>>Hmmm... I'll take a stab at this.
>>
>>Inputs and other data-entry fields and widgets exist solely to collect
>>information from the remote user.  In order for them to work in this
>>capacity, they are collectively grouped together under the heading of a
>>'form', and are sent back to wherever the
>>data processing and analysis is done (usually on a CGI/BIN formserver
>>somewhere).
>>
>>Many of these widgets don't work at all, or don't work properly UNLESS
>they
>>are in a form.  The general structure of a form is as follows:
>>
>>   <body>
>>   ... yada yada
>>     <form name='myForm' action='stuff that points to formserver'
>>type="CGI/BIN" method="POST">
>>       <table>
>>         ... tidy graphical arrangement of input devices
>>       </table>
>>     </form>
>>   ... yada yada
>>   </body>
>>
>>   Obviously, a lot more can be said.  If you want to use the form only
>for
>>the active data widgets and not to actually go anywhere, you can throw
>away
>>the type and method declaractions, and change the action as follows:
>>
>>   action='javascript:void(null)'
>>
>>   There, does that answer your question?
>>
>>   -- Dave Lovering
>>
>>BEKIM BACAJ wrote:
>> >
>> > Thanks, Rodney.
>> > Now,I would like to ask a question on what 'form' stands for?
>> > Also are you sugesting that my script will not work faster than
>your's,
>>or,
>> > that my script will not work at all?
>> >
>> > Bekim
>> >
>> > >From: Rodney Myers <rodney at aflyingstart.net>
>> > >Reply-To: "[JavaScript List]" <javascript at LaTech.edu>
>> > >To: "[JavaScript List]" <javascript at LaTech.edu>
>> > >Subject: Re: [Javascript] required entry field
>> > >Date: Fri, 28 Mar 2003 10:11:19 +0000
>> > >
>> > >That would be .....
>> > >
>> > >function isValid(form) {  if(form.NeverBlank.value=='')
>> > >   {
>> > >    form.NeverBlank.focus()
>> > >   }
>> > >}
>> > >
>> > >hth
>> > >Rodney
>> > >
>> > >
>> > >
>> > >BEKIM BACAJ wrote:
>> > >
>> > >>Einstein went mad when he heard that somebody wrote SF novel about
>a
>>man
>> > >>who traveled with the speed of light and saw the batle of Waterloe,
>>for it
>> > >>is insaine he yelled.
>> > >>But 'you' can init the new battle at Waterlloe again
>> > >>
>> > >>function isValid() {    if(NeverBlank.value==''){
>> > >>         NeverBlank.focus()
>> > >>                 }
>> > >>         }
>> > >>
>> > >>dejavoo - loops forever - if the user does not supply some chars!
>> > >>
>> > >
>> > >--
>> > >PS. I have just bought a licence for Mike Chen's
>> > >BizAutomator. If you have to answer routine email queries from your
>>sites
>> > >or mailings then
>> > >you need this as much as I do. http://www.BizAutomator.com/rlbm51
>> > >
>> > >Rodney
>> > >
>> > >
>> > >
>> > >
>> > >_______________________________________________
>> > >Javascript mailing list
>> > >Javascript at LaTech.edu
>> > >https://lists.LaTech.edu/mailman/listinfo/javascript
>> >
>> > _________________________________________________________________
>> > Protect your PC - get McAfee.com VirusScan Online
>> > http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963
>> >
>> > _______________________________________________
>> > Javascript mailing list
>> > Javascript at LaTech.edu
>> > https://lists.LaTech.edu/mailman/listinfo/javascript
>>_______________________________________________
>>Javascript mailing list
>>Javascript at LaTech.edu
>>https://lists.LaTech.edu/mailman/listinfo/javascript


_________________________________________________________________
Add photos to your messages with MSN 8. Get 2 months FREE*.
http://join.msn.com/?page=features/featuredemail

_______________________________________________
Javascript mailing list
Javascript at LaTech.edu
https://lists.LaTech.edu/mailman/listinfo/javascript

More information about the Javascript mailing list