Develop Reference

remove time and timezone from DateTimeOffset

my goal => 5/26/2022
but I can't remove time from date. => 5/26/2022 12:00:00 AM
How can I remove the time without using ToShortDateString()?
Value.Date.ToShortDateString()
Example;
https://dotnetfiddle.net/xWELRP

If you are using .Net6, then you can use DateOnly struct,
var dateOnly = DateOnly.FromDateTime(DateTimeOffset.Now.Date);
Console.WriteLine(dateOnly);
.Net Fiddle

You could try with
DateTime.Now.Date
if your variable is type of DateTime,itwould have hour minute and second by default,it would set the time to 0:00:00

You can just write like this:
Console.WriteLine($"{data:d}");
There are a few other format constraint keywords where you can find the one that works best for you, this is a very easy way to do it.

How to get date last week date from today date in c# [duplicate]

I have the following code in my C# program.
DateTime dateForButton = DateTime.Now;
dateForButton = dateForButton.AddDays(-1); // ERROR: un-representable DateTime
Whenever I run it, I get the following error:
The added or subtracted value results in an un-representable DateTime.
Parameter name: value
Iv'e never seen this error message before, and don't understand why I'm seeing it. From the answers Iv'e read so far, I'm lead to believe that I can use -1 in an add operation to subtract days, but as my question shows this is not the case for what I'm attempting to do.

DateTime dateForButton = DateTime.Now.AddDays(-1);

That error usually occurs when you try to subtract an interval from DateTime.MinValue or you want to add something to DateTime.MaxValue (or you try to instantiate a date outside this min-max interval). Are you sure you're not assigning MinValue somewhere?

You can do:
DateTime.Today.AddDays(-1)

You can use the following code:
dateForButton = dateForButton.Subtract(TimeSpan.FromDays(1));

The dateTime.AddDays(-1) does not subtract that one day from the dateTime reference. It will return a new instance, with that one day subtracted from the original reference.
DateTime dateTime = DateTime.Now;
DateTime otherDateTime = dateTime.AddDays(-1);

Instead of directly decreasing number of days from the date object directly, first get date value then subtract days. See below example:
DateTime SevenDaysFromEndDate = someDate.Value.AddDays(-1);
Here, someDate is a variable of type DateTime.

The object (i.e. destination variable) for the AddDays method can't be the same as the source.
Instead of:
DateTime today = DateTime.Today;
today.AddDays(-7);
Try this instead:
DateTime today = DateTime.Today;
DateTime sevenDaysEarlier = today.AddDays(-7);

I've had issues using AddDays(-1).
My solution is TimeSpan.
DateTime.Now - TimeSpan.FromDays(1);

Using AddDays(-1) worked for me until I tried to cross months. When I tried to subtract 2 days from 2017-01-01 the result was 2016-00-30. It could not handle the month change correctly (though the year seemed to be fine).
I used date = Convert.ToDateTime(date).Subtract(TimeSpan.FromDays(2)).ToString("yyyy-mm-dd");
and have no issues.

Taking a DateTime value and only accepting time and vice versa

I'm currently developing an application to function as a todo - list and i was wondering how do i accept a Value from a date time box, but only use the value of the date, or the value of the time. I'm currently doing it like this.
DateTime ted = appointmentDateTimeDate.Value; //The date
DateTime at = appointmentDateTimeTime.Value; //The time
should i be doing this another way?

Use DateTime.Date property for date, and DateTime.TimeOfDay for time:
DateTime ted = appointmentDateTimeDate.Date; //The date
TimeSpan at = appointmentDateTimeTime.TimeOfDay; //The time

The BCL doesn't really separate dates and times nicely.
If you're happy to take a new external dependency, I'd like to plug my Noda Time library, which will let you separate things out clearly into LocalDate and LocalTime. To perform the conversion from a date/time picker you'd probably use:
var dateAndTime = LocalDateTime.FromDateTime(appointmentDateTimeDate.Value);
LocalDate date = dateAndTime.LocalDate;
LocalTime time = dateAndTime.LocalTime;

Like others pointed out a DateTime always has both a date and a time component. So although it's possible to save both independently using two DateTime, in most cases it's recommendable to save both together in a single DateTime instance.
You should see if you really need both values separated or if your application could combine both in one property, which will make things easier.

A DateTime value ALWAYS contains both the date and the time, whether you use both or not.
You can use the .Date property of a DateTime to get "just the date". it will still have a time value, but the time value will be midnight. You can also use the .TimeOfDay property to get the time portion, which will be a TimeSpan indicating the number of ticks since midnight.
I'm taking a leap here and assuming you're trying to set the date with one control an d the time with another in the UI. Here's a sample of some code we use to do this using an Ajax CalendarExtender attached to a textbox and a custom TimePicker control.
DateTime dt;
try
{
dt = Convert.ToDateTime(txtViewDate.Text).AddHours(txtViewTime.Hour).AddMinutes(txtViewTime.Minute);
if (txtViewTime.AmPm == MKB.TimePicker.TimeSelector.AmPmSpec.PM)
{
dt = dt.AddHours(12);
}
System.Diagnostics.Debug.WriteLine(dt.ToString());
}
catch (Exception)
{
// abort processing
return;
}

Whats the easiest way in C# to define a time of day, i.e. HH:MM:SS, without resorting to DateTime which requires year,month,day?

I'd like to define a time of day, without necessarily specifying a year, month, day, which would require DateTime.
After I define this Time, I'd like to use all of the nice things about DateTime, i.e. AddMinutes, AddHours, .Hour, .Second, etc.
I guess what I really want the "Time" out of "DateTime", but I can't seem to find it anywhere.
Many thanks in advance!
EDIT:
This is what I was looking for:
// Specify a time of day.
TimeSpan timeSinceMidnight= new TimeSpan(16,00,00); // 4pm
... other code to calculate correct date ...
// Work out scheduled time of day.
DateTime date = new DateTime(2010,12,10).Add(timeSinceMidnight);

Why not just use the standard .NET DateTime class and ignore the date part? It seems that DateTime.ToShortTimeString() could help, or perhaps DateTime.TimeOfDay, which returns a TimeSpan representing the length of time since midnight.
Any other solution would be reinventing the wheel.

Take a look at the TimeSpan structure

Lets say you have a datetime stored somewhere such as a database or you stored it in a variable manually. To strip out the time you can use this.
string.Format("{0:MM/dd/yy}");
edit: oops you meant keep the time not the date.

Briefest way to display TimeSpan value as an elapsed time e.g. 1:45:33

I'd like an easy way to display any TimeSpan as an elapsed time without using loops or custom logic
e.g.
hours : minutes : seconds
I'm sure there must be a .NET built-in or format string that applies, however I'm unable to locate it.

The question itself isn't a duplicate but the answer, I assume, is what you are looking for - Custom format Timespan with String.Format. To simplify your solution further you could wrap that functionality up in an extension method of Timespan.

What's wrong with TimeSpan.ToString()?
EDIT: You can use a DateTime as an intermediate formatting store:
TimeSpan a = new TimeSpan(1, 45, 33);
string s = string.Format("{0:H:mm:ss}", new DateTime(a.Ticks));
Console.WriteLine(s);
Not pretty but works.

You can use:
TimeSpan t = TimeSpan.FromSeconds(999);
string s = t.ToString("c"); // s = "00:16:39"
For custom formats, see this MSDN page.

Here is a method I use for custom formatting:
TimeSpan Elapsed = TimeSpan.FromSeconds(5025);
string Formatted = String.Format("{0:0}:{1:00}:{2:00}",
Math.Floor(Elapsed.TotalHours), Elapsed.Minutes, Elapsed.Seconds);
// result: "1:23:45"
I don't know if that qualifies as "without custom logic," but it is .NET 3.5 compatible and doesn't involve a loop.

Use This: .ToString()
According to MSDN, the default format this displays is [-][d.]hh:mm:ss[.fffffff]. This is the quickest and easiest way to display TimeSpan value as an elapsed time e.g. 1:45:33
If you have days, fractions of a second, or a negative value, use a custom format string as described in MSDN. This would look like .ToString(#"hh\:mm\:ss")
Example:
TimeSpan elapsed = new TimeSpan(0, 1, 45, 33);
Console.WriteLine(elapsed.ToString()); //outputs: "1:45:33"
Console.WriteLine(elapsed.ToString(#"hh\:mm\:ss"));//outputs: "1:45:33"