C# Linq Select Distinct By Property Code Example

Example 1: c# distinct comparer multiple properties

List distinctPeople = allPeople   .GroupBy(p => new {p.PersonId, p.FavoriteColor} )   .Select(g => g.First())   .ToList();

Example 2: c# distinct comparer multiple properties

public static IEnumerable DistinctBy     (this IEnumerable source, Func keySelector) {     HashSet seenKeys = new HashSet();     foreach (TSource element in source)     {         if (seenKeys.Add(keySelector(element)))         {             yield return element;         }     } }