C# Datetime is increasing by 3 hours

Question

My dates are being stored in sql server.

Windows server region and timezone are correct, but when I see the date in database it's increased by 3 hours, I think it is comming from some server configuration that is overriding, but don't know where else to look.

When I send date from local project to production database, it saves correctly, but when I use production website it doesn't.

Where else should I check to solve this?

Answer 1

It depends on the codebase running your production portal.

Use Datetime as utc and cater for it accordingly. Or add DatetimeOffset and calculate the difference when needed.

If you still have the luxury of refactoring, I advise you to take a little dive into the Dates and time handling, get a solid understanding of it, then code accordingly, so it doesn't fire back on you in later stages or usages.

Answer 2

If you want to get advantage of your local machine timezone you can use myDateTime.ToUniversalTime() to get the UTC time from your local time or myDateTime.ToLocalTime() to convert the UTC time to the local machine's time.

// convert UTC time from the database to the machine's time
DateTime databaseUtcTime = new DateTime(2011,6,5,10,15,00);
var localTime = databaseUtcTime.ToLocalTime();

// convert local time to UTC for database save
var databaseUtcTime = localTime.ToUniversalTime();

If you need to convert time from/to other timezones, you may use TimeZoneInfo.ConvertTime() or TimeZoneInfo.ConvertTimeFromUtc().

// convert UTC time from the database to japanese time
DateTime databaseUtcTime = new DateTime(2011,6,5,10,15,00);
var japaneseTimeZone = TimeZoneInfo.FindSystemTimeZoneById("Tokyo Standard Time");
var japaneseTime = TimeZoneInfo.ConvertTimeFromUtc(databaseUtcTime, japaneseTimeZone);

// convert japanese time to UTC for database save
var databaseUtcTime = TimeZoneInfo.ConvertTimeToUtc(japaneseTime, japaneseTimeZone);