How to subtract one DateTime from Another and return a double of hours passed

Question

So I have two DateTimes: date1 = 1/1/2000 12:00:00 AM date2 = 1/1/2000 12:30:00 AM

How can I subtract date2 from date1 and return a double of .5?

possible duplicate of [How to subtract a datetime from another datetime?](http://stackoverflow.com/questions/5177002/how-to-subtract-a-datetime-from-another-datetime) — Zong, Nov 06 '13 at 19:45

score 7 · Accepted Answer · edited Nov 06 '13 at 20:03

7

You can subtract one DateTime from another using the - operator (or use the Subtract method) to get a TimeSpan, then use TimeSpan.TotalHours:

DateTime start = new DateTime(2000, 1, 1, 0, 0, 0);
DateTime end = new DateTime(2000, 1, 1, 0, 30, 0);
TimeSpan difference = end - start;
Console.WriteLine(difference.TotalHours); // 0.5

Note that you do not want TimeSpan.Hours, which returns an int in the range -23 to 23 (inclusive); it's the "whole" number of hours.

edited Nov 06 '13 at 20:03

Zong

6,160
5
32
46

answered Nov 06 '13 at 19:43

Jon Skeet

1,421,763
867
9,128
9,194

This won't return an int? I was under the impression TimeSpan only returned int's. – Al Woods Nov 06 '13 at 19:47
3

@AlWoods: Just follow the link to the documentation... (`Hours` returns an `int`; `TotalHours` returns a `double`.) – Jon Skeet Nov 06 '13 at 19:47
Ah. thats where the confusion is coming from! I'll accept asap – Al Woods Nov 06 '13 at 19:48
1

Tried to fix typo in code (TimeStamp -> TimeSpan) but couldn't because "edits must be at least 6 characters". – Jeff Roe Nov 06 '13 at 19:54

DROP TABLE users · Answer 2 · 2013-11-06T19:52:04.060

0

To get the double you have to use TimeSpann.TotalHours, as Suggested by Jon Skeet:

TimeSpan timeSpann = date2 - date1;
Double difference = timeSpann.TotalHours;

TimeSpann.TotalHours

edited Nov 06 '13 at 19:52

answered Nov 06 '13 at 19:44

DROP TABLE users

1,955
14
26

How to subtract one DateTime from Another and return a double of hours passed

2 Answers2