Using IEnumerable and GetEnumerator

[Magnus.Moraberg@gmail.com]

Hi,

I have the following class snippet -

public class ResultsForTestC ases : IEnumerable
{
public int Length
{
get { return resultsForTestC ases.Length; }
}

IEnumerator IEnumerable.Get Enumerator() { return
resultsForTestC ases.GetEnumera tor(); }
ResultsForTestC ase[] resultsForTestC ases;
}

The problem though is if resultsForTestC ases is null, then
resultsForTestC ases.GetEnumera tor() and indeed Length will fail. How
should I handle this.

Thanks,

Barry

[Marc Gravell]

Re: Using IEnumerable and GetEnumerator

Well, what do you want it to do? Personally, I suspect the simplest
option is to default the array to an empty array, perhaps one shared
by all instances (to avoid lots of zero-length arrays):

static readonly ResultsForTestC ase[] EmptyCases = new
ResultsForTestC ase[0];
ResultsForTestC ase[] resultsForTestC ases = EmptyCases;

Otherwise, you have to check for null and return 0 (for length) and
perhaps an empty enumerator (such as EmptyCases.GetE numerator()) if it
is null.

Marc