How to convert linq results to HashSet or HashedSet

Question

I have a property on a class that is an ISet. I\'m trying to get the results of a linq query into that property, but can\'t figure out how to do so.

Basically, look

Answer 1

There is an extension method build in the .NET framework and in .NET core for converting an IEnumerable to a HashSet: https://docs.microsoft.com/en-us/dotnet/api/?term=ToHashSet

public static System.Collections.Generic.HashSet ToHashSet (this System.Collections.Generic.IEnumerable source);

It appears that I cannot use it in .NET standard libraries yet (at the time of writing). So then I use this extension method:

    [Obsolete("In the .NET framework and in NET core this method is available, " +
              "however can't use it in .NET standard yet. When it's added, please remove this method")]
public static HashSet ToHashSet(this IEnumerable source, IEqualityComparer comparer = null) => new HashSet(source, comparer);