Linq to Objects: does GroupBy preserve order of elements?

.net linq group-by
Konstantin Spirin picture Konstantin Spirin · Sep 21, 2009 · Viewed 10.3k times · Source

Does Enumerable.GroupBy from LINQ to Objects preserve order of elements in the groups?

Answer

Konstantin Spirin picture Konstantin Spirin · Sep 21, 2009

Found answer on MSDN: Yes.

The IGrouping<TKey, TElement> objects are yielded in an order based on the order of the elements in source that produced the first key of each IGrouping<TKey, TElement>. Elements in a grouping are yielded in the order they appear in source.

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