Handle negative time spans

Question

In my output of a grid, I calculate a TimeSpan and take its TotalHours. e.g.

(Eval("WorkedHours") - Eval("BadgedHours")).TotalHours

The goal is to show the TotalHours as 39:44, so I need to convert the value from 7.5 to 07:30. This is no problem... unless it's negative!

I can create a TimeSpan object from Hours with

TimeSpan.FromHours( (Eval("WorkedHours") - Eval("BadgedHours")).TotalHours)

If it's negative, I can't convert it to a DateTime to use the .ToString("HH:mm") method, and the TimeSpan object does not support the format string.

Please consider reformatting the code snippets as inline code or code sections, and add the appropriate platform tag (I'd guess .NET from your snippets). — OregonGhost, Jun 19 '09 at 15:42

score 106 · Answer 1 · edited Dec 16 '21 at 18:23

106

Isn't there a TimeSpan.Duration method? I think this would handle what you are trying to do.

Returns a new TimeSpan object whose value is the absolute value of the current TimeSpan object.

edited Dec 16 '21 at 18:23

Jon

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answered Nov 27 '11 at 22:37

Jared

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This is the easiest way, just subtract your two DateTimes, call Duration() on the result, and then do TotalHours. – Dan May 23 '14 at 15:15

score 12 · Answer 2 · answered Jun 19 '09 at 16:14

static string ToHMString(TimeSpan timespan) { 
    if (timespan.Ticks < 0) return "-" + ToHMString(timespan.Negate());

    return timespan.TotalHours.ToString("#0") + ":" + timespan.Minutes.ToString("00");
}

Console.WriteLine(ToHMString(TimeSpan.FromHours(3)));       //Prints "3:00"
Console.WriteLine(ToHMString(TimeSpan.FromHours(-27.75)));  //Prints "-28:45"

This will also work correctly if the timespan is longer than 24 hours.

score 10 · Answer 3 · answered Jun 19 '09 at 15:41

10

Just multiply it by -1 or use an absolute value function.

answered Jun 19 '09 at 15:41

Daniel A. White

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For anyone who googled it: use `TimeSpan.Duration` method. From MSDN: "Returns a new TimeSpan object whose value is the absolute value of the current TimeSpan object". – prostynick Jan 21 '11 at 11:17

score 9 · Answer 4 · edited Jul 29 '16 at 11:26

9

There is a Negate method in the TimeSpan class.

Link to the MSDN documentation: TimeSpan.Negate Method()

edited Jul 29 '16 at 11:26

MCollard

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answered Nov 01 '11 at 11:47

Eugeniu Torica

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score 3 · Answer 5 · edited Jul 11 '13 at 08:39

3

The simple solution would be to do:

string format = "HH:mm";
if(hours < 0)
  format = "-" + format;

hours = Math.Abs(hours)

edited Jul 11 '13 at 08:39

Didier Ghys

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answered Jun 19 '09 at 15:42

Jerod Venema

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score 2 · Answer 6 · answered Jan 02 '15 at 11:26

2

its working .try this

mytimespam.Negate();

answered Jan 02 '15 at 11:26

Deval Patel

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time *spam*, hehe ;) – Jeff B Nov 18 '16 at 14:43

score 1 · Answer 7 · answered Nov 18 '14 at 15:19

Hi i worked this into a bit of code i have been writing, hope it helps

(results) is an int variable

(TimeSpan.FromMinutes(result)) < TimeSpan.Zero ? "-" + TimeSpan.FromMinutes(result).ToString(@"hh\:mm") : "" + TimeSpan.FromMinutes(result).ToString(@"hh\:mm");

score 1 · Answer 8 · edited Feb 20 '18 at 09:33

1

I checked to every where.But i didnt get a correct answer that why i used this way to finish

TimeSpan diff = actualout.Subtract(actualin);
 string a =(diff.ToString()).ToString();
if(a.Contains("-"))
 {        
 diff = new TimeSpan(0,0,0,0);
}

edited Feb 20 '18 at 09:33

Cristik

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answered Feb 20 '18 at 09:04

sajin k

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Much more simple way is to just compare `if (diff < TimeSpan.Zero)` – n0ne Sep 07 '18 at 03:31

score 1 · Answer 9 · edited Jun 22 '19 at 16:02

1

TimeSpan Diff = Date1 - Date2;

if ((int)Diff.TotalDays < 0) { // your code }

edited Jun 22 '19 at 16:02

brcebn

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answered Jun 22 '19 at 13:06

Mohammed Hedach

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Handle negative time spans

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