Daylight Savings in 2007

[Matthew Ireland]

There are changes to Daylight Savings Time in 2007. I have found a posting
on Microsoft.com (http://www.microsoft.com/windows/timezone/dst2007.mspx)
saying that there will be patches for the Operating Systems in mid-November
this year. Does anyone know what is planned for the different .NET versions
(1.0, 1.1 and 2.0) and older runtime environments (for example, VisualC++
and VisualBasic 6.0, VisualStudio 7.0, etc). I looked on both Microsoft.com
and MSDN.Microsoft.com and couldn't find anything pertinent.

This is going to be a large issue with our scheduling programs which use
DateTime in VB, C# and C++. I believe we also have some unmanaged C++ that
use C-runtime and OLEDateTime calculations.

If you have seen something could you please post a URL or other location
that I can use for a report to my management.

Thanks in advance....

 

[Mattias Sjögren]

Does anyone know what is planned for the different .NET versions
(1.0, 1.1 and 2.0) and older runtime environments (for example, VisualC++
and VisualBasic 6.0, VisualStudio 7.0, etc). I looked on both Microsoft.com
and MSDN.Microsoft.com and couldn't find anything pertinent.

Why would these be affected by the change?


Mattias

 

[Dick Grier]

Hi,

I "believe" that this change will affect each OS, not the .NET Framework.
An update to to OS sometime prior to the DST change should take care of it.

Dick

--
Richard Grier, MVP
Hard & Software
Author of Visual Basic Programmer's Guide to Serial Communications, Fourth
Edition,
ISBN 1-890422-28-2 (391 pages, includes CD-ROM). July 2004, Revised March
2006.
See www.hardandsoftware.net for details and contact information.

 

[Jon Skeet [C# MVP]]

Why would these be affected by the change?

All kinds of applications need to know when daylight savings time kicks
in - which is why there's a DaylightTime class in the framework. It'd
be rather a shame if it gave the wrong results...

 

[Cor Ligthert [MVP]]

AFAIK has by instance in the USA the daylight saving not in every state or
county the same rules.

It can be changed every day, I assume that this is on more places in the
world.

It is measured in time only short ago that Brittain took the same rules for
that as the rest as Europe.
(Sorry I should say of course Europe took the same rules as Brittain)

Cor

"Jon Skeet [C# MVP]" <[email protected]> schreef in bericht

Why would these be affected by the change?

All kinds of applications need to know when daylight savings time kicks
in - which is why there's a DaylightTime class in the framework. It'd
be rather a shame if it gave the wrong results...

 

[Mattias Sjögren]

All kinds of applications need to know when daylight savings time kicks

in - which is why there's a DaylightTime class in the framework. It'd
be rather a shame if it gave the wrong results...

Right, but don't you think the DaylightTime class gets its information
from the OS, so that patch would fix it as well?

This isn't the first time the DST changes, it happens all the time in
different countries.


Mattias

 

[Brian Gideon]

AFAIK has by instance in the USA the daylight saving not in every state or
county the same rules.

That's correct. It wasn't even consistent within a state and the rules
have changed at least a half dozen times in the US since 1918. There
were long periods where states could define DST as well. What a mess.
Wikipedia has an excellent article on the topic.

http://en.wikipedia.org/wiki/Daylight_saving_time#United_States

 

[Jon Skeet [C# MVP]]

AFAIK has by instance in the USA the daylight saving not in every state or
county the same rules.

It can be changed every day, I assume that this is on more places in the
world.

I believe in most places it can't be changed on a whim - and it's not
like it happens very often, IMO.

It is measured in time only short ago that Brittain took the same rules for
that as the rest as Europe.
(Sorry I should say of course Europe took the same rules as Brittain)

How long ago was that in software terms? I don't know when it happened,
but I suspect it has less of an impact than it would now...

 

[Jon Skeet [C# MVP]]

Right, but don't you think the DaylightTime class gets its information
from the OS, so that patch would fix it as well?

It might. It might not - certainly in a situation I'm working in we had
to replace the JRE to account for the difference. As MS have more
control over the OS that .NET is installed on, they may well be able to
rely on the OS - but I wouldn't be surprised if *some* change were
needed.

This isn't the first time the DST changes, it happens all the time in
different countries.

I would question "all the time" - I don't think it's that frequent an
occurrence. I know it happened earlier in the year in Australia, but I
don't think it's *that* common.

 

[Cor Ligthert [MVP]]

Jon,

In the rest of the EU it was not such a problem to decide.

http://en.wikipedia.org/wiki/British_Summer_Time

Cor

 

[Cor Ligthert [MVP]]

Ah,

Before we get again a long thread it was in 2002

Cor

Jon,

In the rest of the EU it was not such a problem to decide.

http://en.wikipedia.org/wiki/British_Summer_Time

Cor