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How to get the total hours with different dates in C#

This is my problem now, i want to get the total hours and mins of work.
example from jan. 11 2017 22:00 to Jan. 12 2017 7:00.
so far i have it only work when the end date is not change
DateTime pin = today, pout = DateTime.Parse(empTime);
TimeSpan spanMe = pout.Subtract(pin);
spanMe.Hours
spanMe.Minutes
it gives me negative numbers.

it gives me negative numbers.
That is expected if you subtract a larger item from a smaller item (ie. subtracting a more recent time from an older time). If you always want to see the difference as a positive number and do not want to take into account which is larger then wrap the result of the properties (like .Hours) in Math.Abs (absolute value).
var hours = System.Math.Abs(spanMe.Hours);
var minutes = System.Math.Abs(spanMe.Minutes);
Also as pointed out by #stuartd there is a difference between Hours/Minutes and TotalHours/TotalMinutes. Make sure you are using the correct one for your needs.

It should work :
DateTime pin = DateTime.Parse("jan 11 2017 22:00");
DateTime pout = DateTime.Parse("Jan 12 2017 7:00");
TimeSpan spanMe = pout.Subtract(pin);
Console.WriteLine("Hours : {0}, Minutes : {1}", spanMe.Hours, spanMe.Minutes);
Console.ReadLine();

if you know what is the latest date, you need arrange it accordingly. If not, you can not multiply by -1:
double GetHouers(DateTime one, DateTime another)
{
var diff = (one - another).TotalHours;
return diff > 0 ? diff : diff * -1;
}

You can subtract one DateTime Object from another, and then use .TotalHours property of the DateTime class to get the number of hours. It will give you a double value representing the total hours.
DateTime pin = today, pout = DateTime.Parse(empTime);
double hours = (pout - pin).TotalHours;

DateTime pin = today, pout = DateTime.Parse(empTime);
TimeSpan spanMe = pin.Subtract(pout);
var hours = spanMe.TotalHours;
var minutes = spanMe.TotalMinutes;
You want to use TotalHours and TotalMinutes as these will handle fractions thereof, versus Hours and Minutes which return only whole values. You also need to swap the order of your operands as above for the subtraction step.

Calculate difference between 2 datetimes (Timespan + double)

I have a list that holds Datetimes.
To calculate the difference between 2 DateTime i use TimeSpan.
public static List<DateTime> list = new List<DateTime>();
TimeSpan ts = new TimeSpan();
double result = 0;
ts = DateTime.Now - list[list.Count-1];
result = ts.TotalSeconds;
When debugging this code both the DateTime.Now and the list[list.Count-1] have DateTimes where the DateTime.Now is off course higher then the value of the list.
But for some reason i keep getting 0 in the variable result, how come exactly?
Best regards, Pete

I just tried the following, works perfectly okay.
List<DateTime> list = new List<DateTime>();
list.Add(DateTime.Now.AddDays(-1));
list.Add(DateTime.Now);
list.Add(DateTime.Now.AddDays(1));
TimeSpan ts = new TimeSpan();
double result = 0;
ts = DateTime.Now - list[list.Count - 1];
result = ts.TotalSeconds;
Attached the debbuging picture:
Reasons for not working could be:
Either your list is not being populated
Or the value of ts.TotalSeconds is smaller than double range (Which can be practically not possible.)

First comment, you don't need = new TimeSpan(); - you're only discarding this anyway when you set ts again further down.
What line is your debugger on when you see the value of 0 for result? Have you stepped over the line where result is set? If you are on the line, then that line has not yet actually run...

Instead of using
ts = DateTime.Now - list[list.Count-1];
use
ts=DateTime.Now.Subtract(list[list.Count-1]

I think time difference is to small for seconds, it might be in mili seconds or even smaller. Try ticks like this.
result = ts.Ticks;

There is nothing wrong with the code you have posted (except I would suggest that you join declaration and initialization of your variables). I have to guess but perhaps you are "swallowing" exceptions and pass the empty list?
Then the line
ts = DateTime.Now - list[list.Count-1];
will throw an exception and result will retain it's value of 0.

list doesn't have any elements, so list.Count - 1 doesn't hit anything. also, there might not be an entire second to calculate. i added a time (using ticks) to subtract with. other than that, there's nothing wrong with what you have.
double result = 0;
List<DateTime> list = new List<DateTime>();
list.Add(new DateTime(123456));
TimeSpan ts = DateTime.Now - list[list.Count - 1];
result = ts.TotalSeconds;

How can I segregate properties of DateTime?

I would like to write: if the result of the difference of 2 DateTimes is longer than 3 hours then.... stuff in the if statement happens. But I only need properties in seconds or minutes, can I extract just that from the DateTime object?
if(diffResult > DateTime.Hour(3))
{
}
I also want to know if its possible to divide DateTime by periods. Say I want to split my diffResult (which is the difference between 2 DateTimes) into 3 periods or perhaps for every 3 seconds my counter gets one added to it.

For the first part:
You can subtract two DateTimes to get a TimeSpan there you can get the total of various units - for example:
if ( (secondTime - firstTime).TotalMinutes > 180.0) ...
or you could use TimeSpan directly:
if (secondTime - firstTime > TimeSpan.FromHours(3)) ...
for the secondpart you have to do some calculation yourself:
var diff = secondTime - firstTime;
var period = TimeSpan.FromSeconds(diff.TotalSeconds / 3.0);
for (var time = firstTime; time < secondTime; time += period)
{ /* do your stuff */ }

U can compare using the follow code:
DateTime dt = new DateTime();
dt = DateTime.Now;
dt.AddHours(3);
int h = (int)DateTime.Now.Hour;
if (dt.Hour == h )
//Do something
else
//do otherthing

You can do this:
TimeSpan time = new TimeSpan(3, 0, 0);
if (date1.Subtract(date2) > time)
{
//YourCode
}
For the second, this article should be useful:
http://www.blackwasp.co.uk/TimespanMultiplication.aspx

The methods your asking about return integer results. What exactly is your question? DateTime.Hour(3) would not even compile.
I think you are looking for DateTime.Now.AddHours(3.0)
I should be clear, the only reason this answer is this sparse, is because of the invalid code in the author's question which. Since I don't attempt to guess at what people actually want, its up to the author, to clarify what he wants exactly.
All he has to do is subtract two DateTime values and compare it to a TimeSpan

Check difference in seconds between two times

Hi all I am currently working on a project where when a certain event happens details about the event including the time that the event occurred is added into a list array.
Once the method has finished I then pass on the list to another method that checks its values. Before I go through the loop I check the current time of my PC and I need to check whether the difference between the time saved in the list array and the current time is greater than 5 seconds.
How would I go about doing this.

Assuming dateTime1 and dateTime2 are DateTime values:
var diffInSeconds = (dateTime1 - dateTime2).TotalSeconds;
In your case, you 'd use DateTime.Now as one of the values and the time in the list as the other. Be careful of the order, as the result can be negative if dateTime1 is earlier than dateTime2.

DateTime has a Subtract method and an overloaded - operator for just such an occasion:
DateTime now = DateTime.UtcNow;
TimeSpan difference = now.Subtract(otherTime); // could also write `now - otherTime`
if (difference.TotalSeconds > 5) { ... }

This version always returns the number of seconds difference as a positive number (same result as #freedeveloper's solution):
var seconds = System.Math.Abs((date1 - date2).TotalSeconds);

I use this to avoid negative interval.
var seconds = (date1< date2)? (date2- date1).TotalSeconds: (date1 - date2).TotalSeconds;

The built-in DateTime.Subtract method can be used as follows
double diffInSeconds = dateTime1.Subtract(dateTime2).TotalSecond;
if (diffInSeconds > 5) { /* do stuff */ } ;

Find the closest time from a list of times

So, here's the scenario. I have a file with a created time, and I want to choose a time from a list of times that that file's created time is closest or equal too...what would be the best way to accomplish this?

var closestTime = listOfTimes.OrderBy(t => Math.Abs((t - fileCreateTime).Ticks))
.First();
If you don't want the performance overhead of the OrderBy call then you could use something like the MinBy extension method from MoreLINQ instead:
var closestTime = listOfTimes.MinBy(t => Math.Abs((t - fileCreateTime).Ticks));

Something like this:
DateTime fileDate, closestDate;
ArrayList theDates;
long min = long.MaxValue;
foreach (DateTime date in theDates)
if (Math.Abs(date.Ticks - fileDate.Ticks) < min)
{
min = Math.Abs(date.Ticks - fileDate.Ticks);
closestDate = date;
}

The accepted answer is completely wrong. What you want is something like this:
DateTime fileDate, closestDate;
List<DateTime> theDates;
fileDate = DateTime.Today; //set to the file date
theDates = new List<DateTime>(); //load the date list, obviously
long min = Math.Abs(fileDate.Ticks - theDates[0].Ticks);
long diff;
foreach (DateTime date in theDates)
{
diff = Math.Abs(fileDate.Ticks - date.Ticks);
if (diff < min)
{
min = diff;
closestDate = date;
}
}

var closestTime = (from t in listOfTimes
orderby (t - fileInfo.CreationTime).Duration()
select t).First();

How often will you be doing this with the same list of times? If you're only doing it once, the fastest way is probably to just scan through the list and keep track of the closest time you've seen yet. When/if you encounter a time that's closer, replace the "closest" with that closer time.
If you're doing it very often, you'd probably want to sort the list, then use a binary search.

get the difference of your file creatime and every time in your list and sort the absolute value of each time difference. the first one should be the answer you are looking for.

Use the minimum absolute time difference between the file time and the time in the list. You might get 2 entries being the same, and then you would need a different method to differ between these.

Not an answer, but a question regarding the various LINQ solutions proposed above. How efficient is LINQ? I have not written any "real" programs with LINQ yet, so I'm not sure on the performance.
In this example, the "listOfTimes" collection implies that we have already iterated over some file system based objects to gather the times. Would it have been more efficient to do the analysis during the iteration instead of later in LINQ? I recognize that these solutions may be more "elegant" or nicely abstract the "collection as database" idea, but I tend to choose efficiency (must be readable though) over elagance in my programming. Just wondering if the cost of LINQ might outweigh the elegance here?

var creationTimes = new [] {DateTime.Now.AddDays(-1), DateTime.Now.AddDays(-2)};
FileInfo fi = new FileInfo("C:/test.xml");
var closestTime = creationTimes
.OrderBy(c => Math.Abs(c.Subtract(fi.CreationTime).Days))
.First();

var min = listoftimes.Select(
x => new { diff = Math.Abs((x - timeoffile).Ticks), time = x}).
OrderBy(x => x.diff).
First().time;
Note: Assumes at least 1 entry in listoftimes.

I thought I would update this post to include a real world scenario. I wanted this sort of function as I have a blog showing news of the latest movie screenings.
However I don't want to list screening in the past (ie screening date past the current date) and as I wanted to show a record I needed some sort of ID passed to pick up the record.
I have left if simple so that you can follow the process and no doubt make it more efficient with LINQ et al.
First the model
public class LatestScreeeningsModel
{
public int Id { get; set; }
public DateTime Date { get; set; }
}
Then the code block you can call from your controller
private static LatestScreeeningsModel GetLatestScreening(IPublishedContent currentNode)
{
LatestScreeeningsModel latestScreening = new LatestScreeeningsModel();
DateTime fileDate;
// get a list of screenings that have not shown yet
var screenings = currentNode.AncestorsOrSelf("siteLanguage")
.FirstOrDefault().Descendants("screening")
.Select(x => new LatestScreeeningsModel() { Id = x.Id, Date = x.GetPropertyValue<DateTime>("date") })
.Where(x => x.Date > DateTime.Now).ToList();
fileDate = DateTime.Today;
long min = Math.Abs(fileDate.Ticks - screenings[0].Date.Ticks);
long diff;
foreach (var comingDate in screenings)
{
diff = Math.Abs(fileDate.Ticks - comingDate.Date.Ticks);
if (diff <= min)
{
min = diff;
latestScreening = comingDate;
}
}
return latestScreening;
}
I am using Umbraco to get the date items but it would work with any custom model, List et al.
Hope it helps

This is a generalized solution to the question, "Find the closest time from a list of times". This solution finds the closest time before and after a given search time.
//For finding the closest time in a list using a given search time...
var listOfTimes = new List<DateTime>();
listOfTimes.Add(DateTime.Parse("1/1/2000"));
listOfTimes.Add(DateTime.Parse("1/2/2000"));
listOfTimes.Add(DateTime.Parse("1/3/2000"));
listOfTimes.Add(DateTime.Parse("1/4/2000"));
listOfTimes.Add(DateTime.Parse("1/5/2000"));
var searchTime = DateTime.Parse("1/3/2000");
var closestBefore = listOfTimes.LastOrDefault(t => t < searchTime);
var closestAfter = listOfTimes.FirstOrDefault(t => t > searchTime);
Console.WriteLine(closestBefore);
Console.WriteLine(closestAfter);
/*
searchTime: 1/3/2000
before: 1/2/2000 12:00:00 AM
after: 1/4/2000 12:00:00 AM
searchTime: 1/1/1900 (edge case)
before: 1/1/0001 12:00:00 AM (DateTime.MinValue)
after: 1/1/2000 12:00:00 AM
searchTime: 1/1/2001 (edge case)
before: 1/5/2000 12:00:00 AM
after: 1/1/0001 12:00:00 AM (DateTime.MinValue)
*/