Re: Timer on webpages

RobG said the following on 4/29/2006 10:54 PM:
> Randy Webb wrote:
>> Dr John Stockton said the following on 4/29/2006 5:25 PM:
>>> JRS: In article <mM2dnd6tB8szLM7ZnZ2dnUVZ_vidnZ2d@comcast.com>, dated
>>> Sat, 29 Apr 2006 14:34:28 remote, seen in news:comp.lang.javascript,
>>> Randy Webb <HikksNotAtHome@aol.com> posted :
>>>>> In the callback you update the counter, animation, etc., and
>>>>> increment a variable that counts how many seconds have elapsed.
>>>> I don't agree with that one. Incrementing a variable would lead to
>>>> inaccuracies in the total. Just start with a Date object and compare
>>>> the current time, get the difference, and display it.
>>>
>>> Using a Date Object to indicate duration will be unreliable in systems
>>> where the clock is being automatically synchronised from time to time.
>>
>> If your app is that time critical, then you would know whether that
>> was happening or not and if you didn't allow for it then you get what
>> you deserve.
>
> Absolutely, so worth mentioning.
>
>
>>> Using a Date Object naively to indicate duration will be unreliable when
>>> the season changes between Summer and Winter.
>>
>> And naively assuming that most business applications are being used on
>> a Saturday night at 2AM is indeed naive.
>
> That is not naive at all - many businesses that have a production
> process have shift work. I've frequently been involved in projects with
> 24hr shifts, 7 days per week over many months. That is common on
> projects such as those that use very expensive CAD equipment, say a
> major construction project.

True, but that falls into the first category. That is a time critical
application and if you don't take care to account for it then you, well,
deserve what you get :)

But, your point is valid.

But, most sites that have a count-down/up timer are not business apps.
Some are, but most aren't. Probably a quiz type site that the OP has.

-- 
Randy
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