How do I Mapper.Map for IGrouping

Question

I'm having a problem when use AutoMapper

my code:

public static IQueryable<IGrouping<Int64, GroupTimeSheetViewModel>> ToListGroupViewModel(this IQueryable<IGrouping<Int64, GroupTimeSheet>> entity)
    {
        return Mapper.Map<IQueryable<IGrouping<Int64, GroupTimeSheet>>, IQueryable<IGrouping<Int64, GroupTimeSheetViewModel>>>(entity);
    }

when I run my code, I get error:

The value "System.Collections.Generic.List1[PG.Admin.Models.TimeSheetHeaders.GroupTimeSheetViewModel]" is not of type "System.Linq.IGrouping2[System.Int64,PG.Admin.Models.TimeSheetHeaders.GroupTimeSheetViewModel]" and cannot be used in this generic collection. Parameter name: value

check this question:http://stackoverflow.com/questions/13305391/mapping-a-grouped-collection-using-automapper — Ehsan Sajjad, Jan 08 '15 at 04:42

score 2 · Accepted Answer · edited Sep 05 '17 at 14:25

2

AutoMapper can't map queryables directly. If I were you, I'd use AutoMapper's LINQ projection capabilities. It uses LINQ to build out the Select projection. That way, your resultant LINQ would be something like:

dbContext.GroupTimeSheets
   .GroupBy(ts => ts.Something)
   .Project().To<GroupTimeSheetViewModel>()
   .ToListAsync();

edited Sep 05 '17 at 14:25

Merilynn Bandy

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answered Mar 11 '15 at 02:54

Jimmy Bogard

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How do I Mapper.Map for IGrouping

1 Answers1