https://learn.microsoft.com/en-us/dotnet/api/system.collections.specialized.nameobjectcollectionbase.basehaskeys?view=netframework-4.8
NameObjectCollectionBase.BaseHasKeys Method (System.Collections.Specialized) | Microsoft Learn
Gets a value indicating whether the NameObjectCollectionBase instance contains entries whose keys are not null.
methodsystemcollectionsspecializedmicrosoft