c# - Create a list of objects by grouping on multiple properties -


i have list<t> t custom object cow. right use following code split list based on color.

cowgroups = x in cows             group x x.color y             select y.tolist().tolist();

then take cowgroups , run foreach on set of actions each cow. list comes out ienumerable<list<cow>>

what i'm trying do double grouping on initial list<cow> can group base on color , size. result should still ienumerable<list<cow>>, each list<cow> made based on combined pair of color , size.

a co-worker recommended tolookup approach, returns list of key/value pairs, , can't seem value part of pair.

i guess i'm looking either way go straight collection of lists, or turn result of tolookup approach collection of lists.

you can group class contains both attributes:

group x new { x.color, x.size } y

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