The Count property returns the number of data items assigned to an object.
Examples:
The following VBA example creates an ellipse and assigns the number 2 to its Properties collection. It then displays the number of elements in the collection (1).
Sub Test()
Dim s As Shape
Set s = ActiveLayer.CreateEllipse(0, 0, 2, 2)
s.Properties("MyMacroParam", 0) = 2
MsgBox s.Properties.Count
End Sub