See Also: OptionValueCollection Members
A Mono.Options.OptionValueCollection instance is tied to a controlling Mono.Options.OptionContext instance, and its behavior is tied to the Mono.Options.Option that the OptionContext.Option property returns.
If OptionContext.Option refers to an Mono.Options.Option with an Mono.Options.OptionValueType of OptionValueType.Optional, then the OptionValueCollection.Item(int) indexer will return null if index is less than Option.MaxValueCount and index is otherwise invalid (i.e. there hasn't been a string Added for that index.
Otherwise, this instance behaves like List<string>.