C# – TimeZoneInfo with current UTC offset

TimeZoneInfo always shows the base UTC offset. This can be confusing because the UTC offset can change based on the date (due to daylight savings rules). Here’s an example showing DateTimeOffset and TimeZoneInfo with different offsets: You can get a date’s UTC offset from DateTimeOffset and combine it with TimeZoneInfo.DisplayName. This approach is implemented in … Read more

C# – How to use TimeZoneInfo

Time zones are complicated and their rules can change, so it makes sense to use a library when you’re dealing with them. One option in .NET is to use the built-in TimeZoneInfo class. Here’s an example of using TimeZoneInfo to get the local system’s time zone: This outputs: Note: The display name always show the … Read more

C# – Get the current date and time

Here’s an example of how to get the current date/time: This outputs the current local date/time: Note: By default, it uses the current culture’s format (from the OS). This is showing the US date format – MM/dd/yyyy. DateTime.Now is the local date/time from the system where the code is executing. Keep that in mind if … Read more

C# – Get the last day of the month

The last day of the month is the number of days in that month. To get the number of days in a month, use DateTime.DaysInMonth(year, month): This outputs the following: Notice that it handles leap years (2024) appropriately. Using the number of days in the month, you can get the last day of the month: … Read more

C# – Parsing a DateTime string with a custom format

In most cases when you need to parse a datetime string with a custom format, you can pass in the format specifier and use DateTime.TryParseExact() (or ParseExact()), like this: This is using the format specifier “M/d/yyyy”. The following code uses use this method: This outputs the following: Notice that it was able to handle month … Read more

C# – How to test that your code can handle another culture’s date format

Let’s say you’re using DateTime.Parse() to convert a date string into a DateTime object. By default, DateTime.Parse() uses CultureInfo.CurrentCulture to figure out the date format. The current culture ultimately comes from your OS settings. So when you run this code on a computer that is using the en-US locale, the current culture will automatically default … Read more