Timezone software

Time Zone. See System Requirements. Available on PC Mobile device. Description I can call the customer in New York? Show More.

People also like. Skype Free. Telegram Messenger Free. Netflix Free. Microsoft Authenticator Free. Windows Insider Free. Spotify Free. I recently came across an issue involving timezones.

There were some unit tests making assertions about dates that used to work at my office in France but weren't working in Morocco for new members on our team. As the earth is kind of a sphere, the sun is rising in Japan while it's setting in America. Not very handy. As a result, the globe gets split into time zones and each gets an offset. This offset is a number of minutes to add to the global time to get your time zone time.

It can be either positive or negative. You may also heard about GMT which is a time zone without any offset. You can check it out on Wikipedia. In addition of this offset, which comes with the time zone, some countries also shift clocks twice a year. DST or summer time adds one hour to the time zone offset before summer. Then, the clock is reset to the time zone time in winter.

The goal is to make the daytime longer. But this can cause issues when running cross-platform. NET Core apps. IANA is still the go-to. The Microsoft database isn't updated often, it contains less history, fairly curious time zone names eg: Romantic Standard Time and is error prone. For more details on each database and their differences, check out this article. One last thing: there are plenty of ways to write a date.

Fortunately, the ISO specification sets a common rule for date formatting. Computers are only able to perform operations using numbers. In order to work with dates more easily, we can represent dates as numbers. This is what timestamps are all about. Actually, the common epoch has already been set and its value is January 1, midnight UTC. To make sure you understood, run the previous snippet in your browser. Fortunately, with some careful planning, it is possible to minimize the trouble caused by time zone complications.

If it ended there, time zones would probably be no big deal. DST causes some time offsets to change based on the date. If handling timestamps in your application is going to break anywhere, it will likely be around the transition to or from Daylight Saving Time. To add to the confusion, the rules regarding the start and end times of DST have changed over the years. Performing any kind of math or comparison on a timestamp by yourself is risky.

Even something as seemingly innocuous as adding 86, seconds 24 hours to a timestamp in order to advance it by one day will break on a DST boundary. DST rules change. Leap years are a thing leap seconds are a thing. And even when using a library, be careful to note which time zone is in effect, as many will default to using the current local time zone if not specified.

Even if you store timestamps using UTC, you may want to designate an official time offset for your application.