System.Data.DataTable.FindNestedParentRelations C# (CSharp) Method

        private DataRelation[] FindNestedParentRelations()
        {
            List<DataRelation> nestedParents = null;
            foreach (DataRelation relation in ParentRelations)
            {
                if (relation.Nested)
                {
                    if (null == nestedParents)
                    {
                        nestedParents = new List<DataRelation>();
                    }
                    nestedParents.Add(relation);
                }
            }

            return (null == nestedParents) || (nestedParents.Count == 0) ?
                Array.Empty<DataRelation>() :
                nestedParents.ToArray();
        }