Tip  TimeSpan Minutes vs TotalMinutes
[C#, TimeSpan, Tips]
The TimeSpan object allows for the representations of a point in time (the TimeOfDay component of a DateTime).
It also allows for computations (subtraction and addition) of TimeSpans
.
What often trips me up (and I suspect I am not alone) is the difference between the Minutes property and the TotalMinutes property; as well as the similar properties:
 Hours vs TotalHours
 Days vs TotalDays
 Seconds vs TotalSeconds
 Milliseconds vs TotalMilliseconds
If you use the interchangeably you can get all sort of strange errors where your code returns the correct results in some situations and the wrong results in others.
Let’s look at some code to illustrate:
var start = new TimeSpan(10, 0, 0);
var firstEnd = new TimeSpan(10, 30, 0);
Console.WriteLine((firstEnd  start).Minutes);
Console.WriteLine((firstEnd  start).TotalMinutes);
The results should be as follows:
[14:55:58 INF] Minutes: 30
[14:55:58 INF] Total Minutes: 30
If we subtract the TimeSpans from each other, the resultant TimeStamp’s relevant properties are as displayed.
Here we can see that they are exactly the same.
Let’s try something different:
var start = new TimeSpan(10, 0, 0);
var secondEnd = new TimeSpan(11, 1, 0);
Log.Information("Minutes: {minutes}", (secondEnd  start).Minutes);
Log.Information("Total Minutes: {minutes}", (secondEnd  start).TotalMinutes);
The results should be as follows:
[14:58:54 INF] Minutes: 1
[14:58:54 INF] Total Minutes: 61
Here we can see that they are different.
So, it seems as follows:

Minutes
is simply a calculation where theMinutes
component of eachTimeSpan
is subtracted from the other. This implies the minimum is 0 and the maximum is 59.In other words, after getting to 59, the
Minutes
cycle back to 0 
TotalMinutes
is a calculation of how many minutes are there between each of theTimeSpans
. This implies for all intents and purposes, there isn’t a maximum.
Additionally, seconds and milliseconds factor into the TotalMinutes
computation:
var thirdEnd = new TimeSpan(0, 12, 0, 30, 0);
Log.Information("Minutes: {minutes}", (thirdEnd  start).Minutes);
Log.Information("Total Minutes: {minutes}", (thirdEnd  start).TotalMinutes);
The results should be as follows:
[15:11:19 INF] Minutes: 0
[15:11:19 INF] Total Minutes: 120.5
Note that the 0.5
is from the 30
seconds in the TimeSpan
constructor we have used (Days, hours, minutes, seconds, milliseconds)
If we add milliseconds we can see the impact:
var fourthEnd = new TimeSpan(0, 12, 0, 30, 0);
Log.Information("Minutes: {minutes}", (fourthEnd  start).Minutes);
Log.Information("Total Minutes: {minutes}", (fourthEnd  start).TotalMinutes);
The results should be as follows:
[15:16:08 INF] Minutes: 0
[15:16:08 INF] Total Minutes: 120.50083333333333
It is possible to retrieve the smaller units after subtracting the TimeStamps
. Now this is where it gets interesting
var fourthEnd = new TimeSpan(0, 12, 0, 30, 50);
var result = (fourthEnd  start);
Log.Information("Minutes: {minutes}", result.Minutes);
Log.Information("Total Minutes: {minutes}", result.TotalMinutes);
Log.Information("Total Seconds: {seconds}", result.Seconds);
Log.Information("Total MilliSeconds: {milliseconds}", result.Milliseconds);
The results should be as follows:
[15:20:37 INF] Minutes: 0
[15:20:37 INF] Total Minutes: 120.50083333333333
[15:20:37 INF] Total Seconds: 30
[15:20:37 INF] Total MilliSeconds: 50
Now, you might ask why did we use Seconds and Milliseconds instead of TotalSeconds and TotalMilliseconds?
Because using TotalXXXX
will compute, remember, the total difference between the two TimeSpans
in that unit;.
If you in fact change the code to do so, this is the result you will get:
[15:23:07 INF] Minutes: 0
[15:23:07 INF] Total Minutes: 120.50083333333333
[15:23:07 INF] Total Seconds: 7230.05
[15:23:07 INF] Total MilliSeconds: 7230050
So play close attention to what exactly you want to retrieve from your computation.
The code is in my GitHub.
Happy hacking!