如何获得两个日期之间的时差

Question

I want get diffrences Day , Hour and Day between two days.

I use belowe Code :

DateTime LastDate = DateTime.Parse("2/12/2015 11:24:23 AM");
int differenceDay = DateTime.Now.Subtract(LastDate).Days;
int differenceHoure = DateTime.Now.Hour - LastDate.Hour;//returns -11
int differenceMinute = DateTime.Now.Minute - LastDate.Minute;

When I want get Hours its return mines (-11 et).

How can I get positive Diffrence Hour ?

anyone can you help me? I want get Last Dat and show its by string how days afterd now.

Answer 1

You're subtracting component-wise (ie "this hour-of-day minus that hour-of-day, this minute-of-hour minus that minute-of-hour"). Don't do that - it won't work if the current hour-of-day is earlier than the hour-of-day of lastDate , or the same for minute-of-hour - you get a negative value, exactly as you've seen.

Instead, subtract one DateTime from another to get a TimeSpan and use that single TimeSpan for all the components:

DateTime lastDate = DateTime.Parse("2/12/2015 11:24:23 AM");
TimeSpan difference = DateTime.Now - lastDate;
int days = difference.Days;
int hours = difference.Hours;
int minutes = difference.Minutes;

That will still be negative if lastDate is after DateTime.Now , of course.

Note that this will give you a result which is meaningful if you display all three components. For example, it might give you "2 days, 3 hours and 10 minutes". If instead you want to represent the same TimeSpan as "2.194 days" or "51.166 hours" or "3160 minutes" then you can use TotalDays , TotalHours and TotalMinutes .

If you always want a positive TimeSpan - the equivalent of Math.Abs but for TimeSpan you can just use TimeSpan.Duration() :

TimeSpan difference = (DateTime.Now - lastDate).Duration();