Re: Getting current date and time of a particular time zone
[
Date Prev][
Date Next][
Thread Prev][
Thread Next]
[
Date Index]
[
Thread Index]
- Subject: Re: Getting current date and time of a particular time zone
- From: "Yuri Takhteyev" <yuri@...>
- Date: 2008年8月17日 03:31:34 -0700
>> Is there anyway to generate the current date and current time given the
>> time zone?
Below is a slightly modified version of a function that I've been
using for generating time stamps in different time zones.
-----------------------------------------------------------------------------
-- Converts a time stamp (like the one returned by os.time()
-- into the requested format. User some code
-- from http://lua-users.org/wiki/TimeZone)
--
-- @param timestamp timestamp (string)
-- @param format Lua time format (string)
-- @param tzoffset time zone offset as "+hh:mm" or "-hh:mm"
-- (ISO 8601) or "local" [string, optional, defaults
-- to "local"]
-- @param tzname name/description of the time zone [string, optional,
-- defaults to tzoffset, valid XHTML is ok]
-- @return formatted time (string)
-----------------------------------------------------------------------------
function format_time(timestamp, format, tzoffset, tzname)
if tzoffset == "local" then -- calculate local time zone (for the server)
local now = os.time()
local local_t = os.date("*t", now)
local utc_t = os.date("!*t", now)
local delta = (local_t.hour - utc_t.hour)*60 + (local_t.min - utc_t.min)
local h, m = math.modf( delta / 60)
tzoffset = string.format("%+.4d", 100 * h + 60 * m)
end
tzoffset = tzoffset or "GMT"
format = format:gsub("%%z", tzname or tzoffset)
if tzoffset == "GMT" then
tzoffset = "+0000"
end
tzoffset = tzoffset:gsub(":", "")
local sign = 1
if tzoffset:sub(1,1) == "-" then
sign = -1
tzoffset = tzoffset:sub(2)
elseif tzoffset:sub(1,1) == "+" then
tzoffset = tzoffset:sub(2)
end
tzoffset = sign * (tonumber(tzoffset:sub(1,2))*60 +
tonumber(tzoffset:sub(3,4)))*60
return os.date(format, timestamp + tzoffset)
end
Here are a few examples of usage:
> return format_time(os.time(), "!%H:%M:%S %z", "local")
03:26:36 -0700
> return format_time(os.time(), "!%H:%M:%S %z", "local", "PST")
03:26:40 PST
> return format_time(os.time(), "!%H:%M:%S %z", "-04:00", "EST")
06:26:48 EST
> return format_time(os.time(), "!%H:%M:%S %z", "-03:00", "(Rio de Janeiro)")
07:26:54 (Rio de Janeiro)
> return format_time(os.time(), "!%H:%M:%S %z", "-03:00", "BRT")
07:27:05 BRT
> return format_time(os.time(), "!%H:%M:%S %z", "-03:00")
07:27:22 -03:00
> return format_time(os.time(), "!%H:%M:%S %z", "GMT")
10:27:26 GMT
- yuri
--
http://sputnik.freewisdom.org/