getTimezoneOffset() baffles me 1

[SCelia]

Ok I find this handy little function that returns the difference in minutes from GMT. I run it tho and I get 420, i.e 7 hours. I'm 8 hours off GMT (PST). So I change the time zone on my computer to GMT and run the program again. -60. Wierd, so I just need to add 60 to it for some reason. I set the time zone to 1 hour off GMT and I get 60. (add 60 to that and I have 120, which is messed up). I can't make any sense of this. How am I supposed to use getTimezoneOffset to find the timezone of the client? Celia

 

[wray]

The odd hour is likely an adjustment for Daylight Savings Time. You are in the Pacific Standard Time zone but your computer is reporting Pacific Daylight Time (and will for another 4 weeks or so). My understanding is GMT is never adjusted for daylight savings which probably accounts for the -60.

Any calculation using TimezoneOffset to conjure the client's time zone will have to account for daylight savings time adjustments. It may be easier use Date.toString() to get time zone -- for most platforms toString() includes the time zone.

 

[SCelia]

Thanks mate, that solved the problems. Celia