Public ReadOnly Property Keys() As ICollection Implements IDictionary.Keys
    Get

        ' Return an array where each item is a key.
        ' Note: Declaring keyArray() to have a size of ItemsInUse - 1
        '       ensures that the array is properly sized, in VB.NET
        '       declaring an array of size N creates an array with
        '       0 through N elements, including N, as opposed to N - 1
        '       which is the default behavior in C# and C++.
        Dim keyArray() As Object = New Object(ItemsInUse - 1) {}
        Dim n As Integer
        For n = 0 To ItemsInUse - 1
            keyArray(n) = items(n).Key
        Next n

        Return keyArray
    End Get
End Property