Question

I have a List<Fields> collection where the class Fields has the following properties

(Name, Currency, Amount, Date, OtherList) where OtherList is a List

Sample values

Name  Currency  Amount Date         F1    F2    F3  
ABC   XX        12     12 Jan 2013  X     Y     Z  
BCA   YY        11     12 Jan 2013  A     B     C  
ABC   XX        10     13 Jan 2013  X     Y     Z 

Now OtherList object will have the values (X, Y, Z) for record1 and (A, B, C) for record2 et.el

What I need to do is apply an aggregation on the above list on the fields Name, Currency, F1, F2 and F3 so that the result is as follows.

Output

Name  Currency  Amount Date         F1    F2    F3  
ABC   XX        22     13 Jan 2013  X     Y     Z  
BCA   YY        11     12 Jan 2013  A     B     C  

Any idea how I can do this?

Thanks.

Answer 1

You can use LINQ:

var aggrList = list
    .GroupBy(x => new { x.Name, x.Currency, x.F1, x.F2, x.F3 })
    .Select(grp => new {
            Name = grp.First().Name,
            Currency = grp.First().Currency,
            Amount = grp.Sum(x=>x.Amount),
            Date = grp.Max(x=>x.Date),
            F1 = grp.First().F1,    
            F2 = grp.First().F2,    
            F3 = grp.First().F3,    
        });