New DateOnly and TimeOnly Types in .NET 6

I keep finding new little gems in .NET 6. The latest was the DateOnly and TimeOnly structs in .NET 6.

Previous to .NET 6, time was typically represented as a DateTime, a DateTimeOffset, or sometimes a TimeSpan for intervals. DateTime and DateTimeOffset worked, but there are odd situations where you need to represent just a Time or just a Date. Trying to represent a Time in a DateTime can lead to all kinds of odd situations.

Is one DateTime UTC vs Local, etc? What if I just need to do time comparisions, what do I do with the date? What if I don't know the time zone, but what "Kind" of DateTime should I use? The questions abound rather quickly.

Enter the DateOnly and TimeOnly structs.

Examples - DateOnly

If you've used the DateTime type at all, much of this will look similar.

// Parse, also TryParse & TryParseExact is implemented
var date = DateOnly.Parse("2021-12-28");
var today = DateOnly.FromDateTime(DateTime.Now);

// Addition Methods
date.AddYears(1);
date.AddMonths(1);
date.AddDays(1);


// Operator Overloads

var date2 = DateOnly.Parse("2022-12-29);
if (date2 < date) {
    Console.Log("You're early...")
}
if (date2 > date) {
    Console.Log("Your'e late...")
}

Here's a link to the reference documentation: .NET 6 DateOnly Reference

Examples - TimeOnly

Again, this should all be vaguely similar to DateTime.

var earlyMorning = TimeOnly.Parse("1:00AM");
var timeToWakeup = new TimeOnly(7, 0);
var sleepingTime = new TimeOnly(5, 0, 0);

if (sleepingTime.IsBetween(earlyMorning, timeToWakeup)) {
    Console.Log("Time to sleep!")
}

// Addition
sleepingTime.AddHours(1);
sleepingTime.AddMinutes(1);
sleepingTime.AddSeconds(1);

// Or operators which subtraction resolves to a TimeSpan
var timeSpan = timeToWakeup - earlyMorning;
Console.Log(timeSpan.ToString()) // 06:00:00

Here's a link to the reference documentation: .NET 6 TimeOnly Reference

Wrapping Up

While this isn't revolutionary, it does make working with Dates and Times easier. I haven't gone through everything that's possible with these new Types, check out the documentation for a complete list of what methods are available.

Again, it's just another one of those little changes in .NET 6 that will be useful.