I cannot understand or find any information that could explain why there are two different time component output (12p.m and 11 a.m) for the following. Can somebody please explain.
DateTime d1 = new DateTime(2015, 05, 15).ToUniversalTime();
DateTime d2 = new DateTime(2015, 02, 02).ToUniversalTime();
Console.WriteLine(d1.ToString()); //OUTPUTS - 1/05/2015 12:00:00 p.m.
Console.WriteLine(d2.ToString()); //OUTPUTS - 1/02/2015 11:00:00 a.m.
The ToUniveralTime method converts from the local time zone where the code is running, to UTC.
Since time zones can change their offsets from UTC at different times of the year, the value can easily be different between two different dates - especially since one date is in the winter, and the other is in the summer, due to daylight saving time.
See also, the DST tag wiki, and "time zone != offset" in the timezone tag wiki.
Related
see my code which i used to convert Mexico date and time to UTC date and time.
string strDateTime = "25/01/2017 07:31:00 AM";
DateTime localDateTime = DateTime.Parse(strDateTime);
DateTime univDateTime = localDateTime.ToUniversalTime();
ToUniversalTime return UTC 25-01-2017 02:01:00
when again i try to convert the same UTC date and time UTC 25-01-2017 02:01:00 to Mexico local time then i got 24-01-2017 06:01:00
so see 07:31:00 AM becomes 06:01:00 which is not right. so tell me what is missing in my code for which i am getting wrong local time when i convert from utc to Mexico time using timezone info.
see my code which converting from utc to Mexico local time using timezone info.
string strDateTime = "25-01-2017 02:01:00";
DateTime utcDateTime = DateTime.Parse(strDateTime);
string nzTimeZoneKey = "Pacific Standard Time (Mexico)";
TimeZoneInfo nzTimeZone = TimeZoneInfo.FindSystemTimeZoneById(nzTimeZoneKey);
DateTime nzDateTime = TimeZoneInfo.ConvertTimeFromUtc(utcDateTime, nzTimeZone);
You current time zone (UTC+05:30) is different from the time zone you are converting into (UTC-8:00). So you get the difference. There is about 13 hours and 30 minutes difference from your original time zone to the targeted one. 5:30 - (-8) = 13:30.
Subtract 13 hours and 30 minutes from your original date, and then you get 18:01:00, which in 12-hour format is 6PM on the previous day.
Edit:
Instead of hard-coding Mexico time zone, you will need to have a method by which you can determine user's time zone no matter where they are coming from. This is best done using JavaScript as outlined in this answer.
Okay, I didn't know that you were located in India - which changes things a little bit:
You're going to want to utilize the TimeZoneInfo.ConvertTime() API for this one.. Maybe something like :
var dt = new DateTime(2017, 01, 25, 7, 31, 0).ToUniversalTime();
var nzTimeZone = TimeZoneInfo.FindSystemTimeZoneById("Pacific Standard Time (Mexico)");
//var ist = TimeZoneInfo.FindSystemTimeZoneById("India Standard Time");
DateTime nzDateTime = TimeZoneInfo.ConvertTime(dt, TimeZoneInfo.Utc, nzTimeZone);
Your problem is that the Parse is done without specifying the timezone it comes from - therefore the system will use whatever the default is of your computer. It appears that Your computer is NOT in PST. Rather somewhere in India.
Therefore after turning it into a DateTime object you need to convert it to UTC by specifying the PST timezone. There are a few ways to do this:
Specify the timezone offset as part of the string.
Call one of the TimeZoneInfo.ConvertTimeToUtc and specify the timezoneid
Maybe all you want to do is convert between two timezones by calling ConvertTime or ConvertTimeByTimeZoneId.
https://msdn.microsoft.com/en-us/library/bb382770(v=vs.110).aspx
https://msdn.microsoft.com/en-us/library/bb382058(v=vs.110).aspx
string pst = "Pacific Standard Time";
TimeZoneInfo.ConvertTimeBySystemTimeZoneId(currentTime, TimeZoneInfo.Local.Id, pst));
For example: 7:30AM PST should be 1:30 UTC - not 2:30. So that suggests a problem in the initial conversion. 2 AM UTC to PST is indeed 6 PM. Also I noticed your input was 7:31 and you claim it output 2:01 -- does Mexico do 30 minute timezones? I know India does.
I use Google to test conversions by literally searching for "2:01 UTC to PST" and it returns the answer for comparison.
See this other post which shows declaring the input timezone for Parsing. And as stated one does NOT need to convert for DST. Does ConvertTimeFromUtc() and ToUniversalTime() handle DST?
More info on MSDN for TimeZoneInfo: https://msdn.microsoft.com/en-us/library/bb495915(v=vs.110).aspx
New to NodaTime and I chose to use it instead of the BCL libraries because it removes a lot of ambiguity when dealing with dates. However, I can't seem to get it to do what I want. I have a date and time specified by year, month, day, hours, and minutes. I also have two timezones for which I need to display the "clock time". For example, if my input is December 15, 2015 at 3:30 PM and my two timezones are central standard and eastern standard (one hour apart), I expect my output to be
12/15/2015 3:30 PM Central
12/15/2015 4:30 PM Eastern
But I can only seem to get the central (local to me, if that matters) timezone. Here's my code:
var localDateTime = new LocalDateTime(
year: 2015,
month: 12,
day: 15,
hour: 15,
minute: 30,
second: 0
);
var centralTimeZone = DateTimeZoneProviders.Bcl.GetZoneOrNull("Central Standard Time");
var easternTimeZone = DateTimeZoneProviders.Bcl.GetZoneOrNull("Eastern Standard Time");
var centralTime = centralTimeZone.AtLeniently(localDateTime);
var easternTime = easternTimeZone.AtLeniently(localDateTime);
It seems that centralTime and easternTime are both ZonedDateTime objects whose times are 2015-12-10T15:30 with the correct offset i.e. centralTime is -6 and easternTime is -5.)
I just can't figure out how to get the output I want.
It sounds like your initial date/time is actually in Central time - so once you've performed the initial conversion, you can just say "Hey, I want the same instant in time, but in a different time zone" - which isn't the same as "I want a different instant in time for the same local time". You want:
var centralTime = centralTimeZone.AtLeniently(localDateTime);
var easternTime = centralTime.InZone(easternTimeZone);
I am trying to convert to Julian Time Stamp to Date Time. I have the following microseconds time stamp 212302469304212709. As i understand i need to add these milliseconds to the beginning of Julian Calendar (January 1, 4713 B.C., 12:00 (noon)). So i have the following method:
private DateTime GetDateTime(string julianTimeStamp)
{
var julianMilliseconds = Convert.ToDouble(julianTimeStamp)/1000;
var beginningOfTimes = new DateTime(1, 1, 1, 0, 0, 0, 0);
var dateTime = beginningOfTimes.AddMilliseconds(julianMilliseconds).AddYears(-4713).AddMonths(-1).AddDays(-1).AddHours(-12);
return dateTime;
}
Assume i pass 212302469304212709 string as the parameter. The expected result should be 2015/07(July)/01 00:08:24.212. Based on my method, i have almost the same result, but day is not 1, it is 6. Same problem for different time stamps i tested.
Could any one tell me what i am doing wrong? Thanks in advance.
Edited:
This is the exact date time i expect to receive: 2015(year) 7(month) 1(day) 0(hour) 8(minute) 24(second) 212(millisecond) 709(microsecond)
The given timestamp 212,302,469,304,212,709 μs when converted to days (just divide by 86,400,000,000) gives 2457204.505836 days (to six decimal places, which is the best I can do without a lot of extra trouble). Using the Multi Year Computer Interactive Almanac (MICA) written by the United States Naval Observatory, and putting in the free form date 2015(year) 7(month) 1(day) 0(hour) 8(minute) 24(second) 212(millisecond) 709(microsecond), the program calculates exactly the same day count (to six decimal places), proving the time stamp is an accurate Julian date.
One problem with the OP's calculation is trying to use the DateTime class before the earliest supported date, as pointed out by another poster. Also, the OP didn't say if 1 July 2015 was in the Julian or Gregorian calendar, but the MICA calculation proves it is in the Gregorian calendar. Since the OP is working in the Gregorian calendar, the epoch of Julian dates should be stated in the Gregorian proleptic calendar: Noon Universal Time, November 24, 4714 BC. The oft-quoted date January 1, 4713 BC is a proleptic Julian calendar date.
"Proleptic" means a date has been found by beginning at a modern date, who's calendar date is known with absolute certainty, and applying the rules of the chosen calendar backward until the desired date is reached, even though the desired date is before the chosen calendar was invented.
DateTime uses Gregorian calendar, so when you substract years, months and so on you are doing it with that calendar, not the Julian.
Unfortunately DateTime does not support dates before year 1. You can check the library in this post, maybe it helps you.
I have two dates
DateTime date1Z = DateTime.Parse("2014-05-22 23:39:29Z");
DateTime date1ZKind = DateTime.SpecifyKind(DateTime.Parse("2014-05-22 23:39:29Z"), DateTimeKind.Utc);
DateTime date2 = DateTime.Parse("2014-05-22 23:39:29");
DateTime date2Kind = DateTime.SpecifyKind(DateTime.Parse("2014-05-22 23:39:29"), DateTimeKind.Utc);
Console.WriteLine(date1Z);
Console.WriteLine(date1ZKind);
Console.WriteLine(date2);
Console.WriteLine(date2Kind);
Prints
23/05/2014 11:39:29 a.m.
23/05/2014 11:39:29 a.m.
22/05/2014 11:39:29 p.m.
22/05/2014 11:39:29 p.m.
Can someone explain whats going on here?
Using the suffix "Z" is date shorthand for saying that the Date-Time is "Zulu" time which is another word for UTC time. The first two dates are being parsed as UTC, while the last two are being parsed as whatever time is on the computer in question.
So to answer you question of what is going on: the latter two dates are being offset by your local time, which is apparently +12:00 (plus twelve hours), while the first two are not (as they are marked as "Zulu" or UTC time).
You live in New Zealand, which is +12 over UTC. That matches the date difference you are experiencing. As mentioned, the Z stands for UTC.
I am trying to convert times to different time zones, but not the way you're thinking. I need to convert a DateTime that is 9am EST to 9am CST on the UTC for example. The timezones are variable so just adding/subtracting hours doesn't seem correct way to do it with NodaTime
Fri, 21 Feb 2014 21:00:00 EST = 1393034400 Epoch Timestamp
convert to
Fri, 21 Feb 2014 21:00:00 CST = 1393030800 Epoch Timestamp
If I understand the question correctly, it sounds like you're trying to convert a date/time in one time zone to another one that has the same local time and a different time zone; that is, a different point in time.
You can do this with Noda Time by combining the LocalDateTime with the new zone. For example, given something like the following:
Instant now = SystemClock.Instance.Now;
DateTimeZone eastern = DateTimeZoneProviders.Tzdb["America/New_York"];
ZonedDateTime nowEastern = now.InZone(eastern);
nowEastern is the time now in the America/New_York time zone. If we print nowEastern directly to the console, we'll see something like 2014-02-22T05:18:50 America/New_York (-05).
As an aside, "EST" and "CST" aren't time zones: they're non-unique abbreviations for a particular offset within a time zone; America/New_York and America/Chicago are probably representative of what we think of as "Eastern" and "Central", though (or you could use something like UTC-05:00 if you really wanted EST even when daylight savings time was in effect).
Given a ZonedDateTime in any time zone, we can convert it to a ZonedDateTime with the same local time and a specified time zone as follows:
DateTimeZone central = DateTimeZoneProviders.Tzdb["America/Chicago"];
ZonedDateTime sameLocalTimeCentral = nowEastern.LocalDateTime.InZoneStrictly(central);
This gives us a ZonedDateTime with the same local time, but a different time zone. With the input above, the result would be 2014-02-22T05:18:50 America/Chicago (-06).
Note that I'm using InZoneStrictly. This will throw an exception if the local time is ambiguous or invalid (for example, during daylight savings transitions). If that's unacceptable, you could use InZoneLeniently, which picks the earliest valid ZonedDateTime on or after the given local time, or InZone, which allows you to specify your own rules in those cases.
On Msdn website you can find all you need.
Small example:
DateTime dateNow = DateTime.Now;
Console.WriteLine("The date and time are {0} UTC.",
TimeZoneInfo.ConvertTimeToUtc(dateNow));
Go to the link for more details on what you want, I can't give you more with that small description