Number of minutes until an unknown DateTime - c#

If I have a DateTime variable that's set to the future, and I don't know if it's set to Utc or Local time, how can I find the number of minutes until this time? Something like this:
DateTime futureTime;
// futureTime is set to some value...
int minutesUntilFutureTime = futureTime - DateTime.Now;

You want a TimeSpan object
TimeSpan untilFutureTime = futureTime - DateTime.Now;
TimeSpan has a property called minutes and total minutes, total minutes is what you want.
int minutesUntilFutureTime = untilFutureTime.TotalMinutes;
doc https://learn.microsoft.com/en-us/dotnet/api/system.timespan?view=netframework-4.8

DateTime has a Kind property that allows you to determine whether or not the time is Local or UTC.
It also can be Unspecified in which case I think you just have to guess because you don't have enough information.
Another option could be to use the .ToLocalTime() method to force your DateTime to always be expressed a Local DateTime.
DateTime futureTime;
double minutesUntilFutureTime = (futureTime.ToLocalTime() - DateTime.Now).TotalMinutes;

Related

Get Current DateTime C# without hour

Hi I currently have a TimePicker. It returns an object TimeSpan.
What I need to do is to set a DateTimeOffset that is equal to current date plus the TimeSpan from the TimePicker.
How can I actually get the current DateTimeOffset.now that doesn't have a Time on it, only the Date so that I can add the offset to it.
Thanks
As in DateTime object you have a Date property, it returns date part without time (it means time is 00:00:00).
DateTime today = DateTimeOffset.Now.Date;
DateTime result = today + yourTimeSpan;
With this solution will lost Offset information (because Date is a DateTime). To keep it you just need to subtract time part:
DateTimeOffset now = DateTimeOffset.Now;
DateTimeOffset result = now - now.Time + yourTimeSpan;
Or with constructor:
DateTimeOffset now = DateTimeOffset.Now;
DateTimeOffset result = new DateTimeOffset(now.Date + yourTimeSpan, now.Offset);
Can you not just .Date it?
var a = DateTimeOffset.Now.Date;
try using:
DateTime.Today
instead of Now.

Alternative Datetime.Now with only time (21:10)

I was wondering if there's a method or anything which will provide me the current systemtime without the date. I need to use this in a formula and if i want to use the DateTime.NowI have to String.Split this string before I can convert this to a Int.
example: It's 5pm
I want:
'17:00', '5:00', '1700', '500'
Not:
'17:00 PM 29/03/2013'
A DateTime holds the hour and minutes as properties.
var now = DateTime.Now;
var minutes = now.Minute;
var hours = now.Hour;
why cannot you simply format your date i.e.
string CurrentTime = DateTime.Now.ToString("hh:mm:ttt");
I guess what you are looking for is how to format a DateTime correctly.
Look here or here for how this is done.
You could use TimeOfDay. Basically it extracts the time part of a DateTime:
DateTime now = DateTime.Now;
TimeSpan time = now.TimeOfDay;
Do note that unlike the DateTime.Date property, DateTime.TimeOfDay returns a Timespan, not a DateTime.
for "1700" :
date.ToString('HHMM');
Use the DateTime.ToString method:
DateTime dt = DateTime.Now; // Suppose it is currently 5pm
dt.ToString("HH:mm"); // 17:00
dt.ToString("h:mm"); // 5:00
dt.ToString("HHmm"); // 1700
dt.ToString("hmm"); // 500

Convert datetime entered by user to UTC

The user enters a date and a time in separate textboxes. I then combine the date and time into a datetime. I need to convert this datetime to UTC to save it in the database. I have the user's time zone id saved in the database (they select it when they register). First, I tried the following:
string userTimeZoneID = "sometimezone"; // Retrieved from database
TimeZoneInfo userTimeZone = TimeZoneInfo.FindSystemTimeZoneById(userTimeZoneID);
DateTime dateOnly = someDate;
DateTime timeOnly = someTime;
DateTime combinedDateTime = dateOnly.Add(timeOnly.TimeOfDay);
DateTime convertedTime = TimeZoneInfo.ConvertTimeToUtc(combinedDateTime, userTimeZone);
This resulted in an exception:
The conversion could not be completed because the supplied DateTime did not have the Kind property set correctly. For example, when the Kind property is DateTimeKind.Local, the source time zone must be TimeZoneInfo.Local
I then tried setting the Kind property like so:
DateTime.SpecifyKind(combinedDateTime, DateTimeKind.Local);
This didn't work, so I tried:
DateTime.SpecifyKind(combinedDateTime, DateTimeKind.Unspecified);
This didn't work either. Can anyone explain what I need to do? Am I even going about this the correct way? Should I be using DateTimeOffset?
Just like all the other methods on DateTime, SpecifyKind doesn't change an existing value - it returns a new value. You need:
combinedDateTime = DateTime.SpecifyKind(combinedDateTime,
DateTimeKind.Unspecified);
Personally I'd recommend using Noda Time which makes this kind of thing rather clearer in my rather biased view (I'm the main author). You'd end up with this code instead:
DateTimeZone zone = ...;
LocalDate date = ...;
LocalTime time = ...;
LocalDateTime combined = date + time;
ZonedDateTime zoned = combined.InZoneLeniently(zone);
// You can now get the "Instant", or convert to UTC, or whatever...
The "leniently" part is because when you convert local times to a specific zone, there's the possibility for the local value being invalid or ambiguous in the time zone due to DST changes.
You can also try this
var combinedLocalTime = new DateTime((dateOnly + timeOnly.TimeOfDay).Ticks,DateTimeKind.Local);
var utcTime = combinedLocalTime.ToUniversalTime();

How to set current time to a value

I was just wondering if there is a way to get the current time and set it into a value.
If its 12:06 AM.. I want to get that time and set it into currentTime.
Example
float currentTime = 0;
currentTime = 12.06;
As others have mentioned, the DateTime class would be ideal for this, and to work out the difference between 2 date/times:
DateTime end = DateTime.Now;
DateTime start = new DateTime(2011, 12, 5, 12, 6,0);
double hours = (end - start).TotalHours;
The subtraction of DateTime objects results in a TimeSpan object that you can use to see the hours/minutes etc.
try DateTime class
DateTime dt = DateTime.Now;
Is this what you're looking for?
DateTime currentTime;
currentTime = DateTime.Now;
Don't use floats or strings. You can do all kinds of cool things using DateTime.
Here's how you'd get the hours that someone worked:
var clockIn = new DateTime(2011,12,4,9,0,0); // December 4th, 9 AM
var clockOut = new DateTime(2011,12,4,17,0,0); // December 4th, 5 PM
var duration = clockOut - clockIn; // TimeSpan
Console.Write(duration.TotalHours); // 8
A few people have mentioned how, but as a 'better' recommendation you should use
DateTime currentTime = DateTime.UtcNow
Otherwise you have issues when the clocks go back, if your timing code is run on those days. (plus it is far easier to alter the UTC time to local time than it is to convert a '1am' to UTC (as there will be two of them when the clocks go back)
Well if you really what it as a float then try:
var currentDate = DateTime.Now;
float currentTime = float.Parse((currentDate.Hour > 12 ? currentDate.Hour -12 :
currentDate.Hour) + "." + currentDate.Minute);
I wouldn't recommend comparing dates or time with floats. A better options would be to use timespans.
You should be using a Timespan instance for time related values, you can use the flexibility to get the required values like
TimeSpan ts = DateTime.Now.TimeOfDay;
ts.ToString("hh:mm") // this could be what you are looking for
You could then use ts.TotalHours which would give you fractional hours (as a double) else you could construct a string specifically using ts.Hours ..ts.Minutes play around and it could be prove useful.
Try the following:
DateTime StartTime=StartTime value;
DateTime CurrentTime=DateTime.Now;
TimeSpan dt = CurrentTime.Subtract(StartTime);
In dt you will get a working time period.
If you want to have the difference between two times, then do this:
DateTime dateOne = DateTime.Parse(enteredTime);
DateTime dateTwo = DateTime.Now;
TimeSpan difference = dateOne - dateTwo;

Differences between 2 times?

StartCopying = DateTime.Now;
File.Copy(#"C:\Users\sshap5x\Desktop\line4\shiraDebbi\Hackers.avi", #"C:\Users\sshap5x\Desktop\test\Hackers.avi", true);
EndCopying = DateTime.Now;
CopyingTime1 = (endCopying - startCopying).Duration;
What is the problem with my code?
Copying time is TimeSpan object.
The assignments are to StartCopying and EndCopying but your read the data from other variables startCopying and endCopying.
C# is case sensitive.
And also Duration is a method. so you need to use .Duration()
And as suggested in the comments to your question, for better resolution use the Stopwatch class.
// This prints 0.1 (roughly)
DateTime start = DateTime.Now;
Thread.Sleep(100);
var diff = DateTime.Now - start;
Console.WriteLine(diff.TotalSeconds);
In your code (which wouldn't even compile) you use .Duration as a property when it is in fact a method. In any case, you don't need to call Duration at all because the result returned by the subtraction is a TimeSpan containing the difference. You can then get this diff in whatever format you need (milliseconds, seconds, hours, days, etc.).
The only need for the Duration method is if you are unsure whether the result is negative or positive.
Did you forget the () for Duration and capitalisation for the variables EndCopying and StartCopying?
DateTime StartCopying = DateTime.Now;
DateTime EndCopying = DateTime.Now;
TimeSpan CopyingTime1 = (EndCopying - StartCopying).Duration();

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