use of unassigned local variable `total`

Question

I want to have a sum of all intervals , but I write this code I have an error stating: use of unassigned local variable total ?

enter TimeSpan total;
foreach (var grp in query)
{
  TimeSpan interval = TimeSpan.FromMinutes(grp.Minuut); 
  TimeSpan intervalH = TimeSpan.FromHours(grp.Sum);

  interval = interval + intervalH;
  total += interval;
  string timeInterval = interval.ToString();   
  dataGridView2.Rows.Add(i++, grp.Id, grp.Sum, grp.Minuut,timeInterval);
}

Your last edit destroyed your formatting and the `enter TimeSpan` part makes no sense. Can you revert or fix that? — CodesInChaos, Oct 24 '11 at 11:55
declare and initialize 'total' before adding 'interval' to it — Alex, Oct 24 '11 at 12:40

score 7 · Answer 1 · answered Oct 24 '11 at 11:42

Start with:

TimeSpan total = TimeSpan.Zero;

Incrementing a variable that has no value makes no sense. So it's only natural for this to be a compiler error.

While fields get initialized to 0, local variables must be assigned to before they are first read. In your program total += interval; reads total in order to increment it. In the first iteration of your loop it thus wouldn't have been assigned a value.

score 1 · Answer 2 · answered Oct 24 '11 at 11:40

1

total += interval;

Is wrong when total has no value assigned at all... What are you going to add interval too?

answered Oct 24 '11 at 11:40

FailedDev

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I just want to have a total of all rows in my datagridview , the column is filled with a timespan. – Nick_BE Oct 24 '11 at 11:43
@Nick_BE Just initialize it to 0. Or whatever the default C'tor is. – FailedDev Oct 24 '11 at 11:44

score 1 · Answer 3 · answered Oct 24 '11 at 11:42

1

You should initialize total value before use

 TimeSpan total = new TimeSpan();,

then code should work.

answered Oct 24 '11 at 11:42

Kamil Lach

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score 0 · Answer 4 · answered Oct 24 '11 at 11:41

0

No initial value is ever assigned to total. You have to assign a value before you use it.

answered Oct 24 '11 at 11:41

dnuttle

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TimeSpan total = new TimeSpan(0); is what I needed – Nick_BE Oct 24 '11 at 11:46

use of unassigned local variable `total`

4 Answers4