I have been trying to figure out how to determine what time zone the user is in. However, when I use the code below, the hour offset and UTC changes with DST or Daylight Saving Time. I tried to make a forumla to calculate it, but when DST is in effect, my formula does not work. How can I detect if DST is in effect? ...or is there a time that does not change with DST that I can check against in ActionScript?



trace results: 4, 20 (at 16:00 EDT), or
trace results: 5, 21 (at 16:00 EST)

The above is very simple. It's not my clock. It's just an illustration of how I'm trying to trace my time zone.
For example, I am in the Eastern Time Zone. So, during EST or Eastern Standard Time, hoursFromGMT = 5, but during EDT or Eastern Daylight Time, hoursFromGMT = 4. Therefore, I cannot say that if hoursFromGMT == 5 then I am in Eastern Time Zone, because during Eastern Daylight Time the value of hourFromGMT would be 4, thus the forumla would say that I'm in the Atlantic Time Zone.

Now, I could create a function to determine which day of the year it is, knowing ahead of time when DST goes into effect, check against that date, then shift the time zone accordingly, but that's a lot of code just to figure out if DST is in effect or not. There must be a simpler way such as...



Any sort of trick would be helpful! also, if no shortcut is available, even with FLPro8, I would appreciate it someone could paste the code for a function to check to see if the current day is in the DST range. That is of course if you already have it. I'm not asking you to write it up just for me.

Flash doesn't have any means of detecting if DST is in effect or not. Unfortunately, what you suggested may be the solution.

We've had a few questions recently about DST in Flash. Is there something we don't know?? lol

I've had this in my head since the first post came up and apart from using external scripts and writing a script to "brute force" it, I haven't found/thought of a different solution at the moment.

What I'm trying to accomplish is to have a countdown clock that shows how much time a visitor to our website has to call us based upon our business hours. I need to be able to calculate their time zone and if they are in DST so I can display the correct number of minutes left that we are open or even the number of minutes until we open again. I guess it's another day with me and ScriptAssist--my pal.

Thanks for the post.

While trying to google for a solution, I came across this post, and since I think I figured it out, I thought I'd come back and post here. Hopefully you have notifications set so you can see it!

Basically, the two assumptions I made are as follows:
- assume that during the summer period is when clocks are advanced by an hour (if they are)
- assume that July lies within this daylight savings period
- assume that January does NOT lie within this daylight savings period

I think the above assumptions are safe to make. So basically, all I did is compare the offset to a date in january, the offset to a date in july, and the offset now to determine whether daylight savings are in effect.

So if the offset now is the same as the summer offset, AND it's different from the winter offset, then daylight savigns are in effect, otherwise, ti isn't.

Thanks Khuffie! Great info and thanks for coming back to share.


Welcome to dream.in.code!

This seemed to me like it might relate to what you're doing
http://livedocs.adobe.com/flash/9.0/main/00000073.html

I hate to burst any bubbles (and it may not matter to you) but this does not work for the southern hemisphere...