How to return ICollection

Question

I have the below linq currently working, but what I would really like is to return an ICollection<SexyPeopleVM> instead of a list. But I can't get my head around the syntax and other alternative I've tried have failed at runtime.

Is this possible? How can I achieve this?

var o = from s in sexyPeople
                    select new SexyPeopleVM()
                    {
                        id = s.ID,
                        title = s.Title,
                        views = s.Views,
                        url = s.GetFullyQualifiedURL(),
                        friendlyDate = s.DateCreated.AsShortFriendly()
                    };
            List<SexyPeopleVM> list = o.ToList();
            return list;

score 7 · Accepted Answer · answered Dec 11 '13 at 20:10

7

List<T> implements ICollection<T>.
You don't need to do anything.

answered Dec 11 '13 at 20:10

SLaks

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176
1,908
1,964

1

yes. Just specify `ICollection` as your function's return type. – David S. Dec 11 '13 at 20:15

score 4 · Answer 2 · edited May 23 '17 at 12:29

4

As SLaks said, he beat me posting, but I wanted to add, you can make your code a little cleaner also:

return (from s in sexyPeople
                    select new SexyPeopleVM()
                    {
                        id = s.ID,
                        title = s.Title,
                        views = s.Views,
                        url = s.GetFullyQualifiedURL(),
                        friendlyDate = s.DateCreated.AsShortFriendly()
                    }).ToList();

One other thing, get Resharper if you do not have it.

I now use

var list = new List<object>();

instead of:

List<object> list = new List<object>();

A good post as to why to use var.

This is just a coding style buy Resharper cleans up your code quite a bit.

I get in the habit and alot of other cleaner habits, like the two above, thanks to Resharper. I can't live without it now.

edited May 23 '17 at 12:29

Community

1
1

answered Dec 11 '13 at 20:11

ErocM

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24
94
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Alternatively, `sexyPeople.Select(s => new SexyPeopleVM(){...}).ToList()` – David S. Dec 11 '13 at 20:12
yeah true, that just seems to confuse people who are newer to C# so I don't use that unless I have to. – ErocM Dec 11 '13 at 20:15
Your code won't compile. The change that you made to simplify it was invalid. – Servy Dec 11 '13 at 20:21

score 1 · Answer 3 · answered Dec 11 '13 at 20:15

1

If you really want the ICollection specifically, just do

 return o.ToList() as ICollection<SexyPeopleVM>;

answered Dec 11 '13 at 20:15

Nathan

64
3

How to return ICollection

3 Answers3

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