ToLookup< TSource, TKey, TElement >() [2/2]

static ILookup< TKey, TElement > System.Linq.Enumerable.ToLookup< TSource, TKey, TElement > ( this IEnumerable< TSource > source, Func< TSource, TKey > keySelector, Func< TSource, TElement > elementSelector, IEqualityComparer< TKey >? comparer )

inlinestatic

Definition at line 5357 of file Enumerable.cs.

    {
        if (source == null)
        {
            ThrowHelper.ThrowArgumentNullException(ExceptionArgument.source);
        }
        if (keySelector == null)
        {
            ThrowHelper.ThrowArgumentNullException(ExceptionArgument.keySelector);
        }
        if (elementSelector == null)
        {
            ThrowHelper.ThrowArgumentNullException(ExceptionArgument.elementSelector);
        }
        return Lookup<TKey, TElement>.Create(source, keySelector, elementSelector, comparer);
    }

References System.comparer, System.Linq.elementSelector, System.Linq.keySelector, System.Linq.source, and System.Linq.ThrowHelper.ThrowArgumentNullException().